Cultural heritage is now considered one of the key factors in the strategic development of territories, as a recognized driver of economic growth, wealth creation, and employment ^[1][2][3][1,2,3]. Moreover, there are several studies (e.g., ^[4][5][6][7][4,5,6,7]) that have addressed the ability of heritage sites to generate wealth via the brand equity of a heritage brand.

Building strong brands, with high brand equity, is one clear way to establish competitive advantage. Researchers and marketing specialists therefore consider brand equity a key strategic asset for organizations [8]. However, the first research on brand equity in relation to tourist destinations was carried out by [9] in 2007 [10]. Since then, tourist destinations have been operating in an increasingly competitive environment; hence, they are obliged to generate competitive advantages. Therefore, research on destination brand equity should be expanded [10].The widespread interest in brand equity since the 1990s, both from academia and the business sector, has given rise to extensive academic literature on the topic and, therefore, to a wide variety of approaches and methodologies for measuring it and identifying its antecedents and consequences ^{[11][12][13][14][15][16]}[11,12,13,14,15,16].

Brand equity is a key construct in brand management ^[8][11][8,11]. Brand equity has been recognized as the means to differentiate a company’s products and services from its competitors [11]. Brand equity is defined as “a set of assets and liabilities linked to a brand, its name and its symbol that add to, or subtract from, the value provided by a firm’s product or service to its clients” [11]. This multidimensional model differentiates between several assets—notably, brand knowledge (awareness), perceived brand quality, brand associations, brand loyalty, and other assets specific to the brand. In general, studies regarding a destination brand consider the consumer-based brand equity model (CBBE) based on the work developed by [11].

When classifying heritage marketing, some doubts about its classification may be encountered from the perspective of the intention to make a profit. In this respect, it instead is classified as a form of non-profit marketing and it is argued that the primary motivation for its implementation should be the preservation or renewal of cultural and natural heritage. The production of profit in a commercial sense (expressed as a monetary benefit) is considered as a means to help achieve this goal. Therefore, many non-profit organizations working in the field of cultural and natural heritage conservation are forced to “generate profit” through additional commercial activities such as providing retail activities (most often the sale of souvenirs), restaurants, catering stalls, the organization of various commercial events, or other paid services clearly belonging to the field of profit marketing. The dichotomy of profit and non-profit objectives of heritage marketing represents its key problem area when setting the marketing mix. It turns out that the sustainability of the development of a tourist destination in such a case depends on the ability to optimize the intensity of development in such a way that the balance of the whole tourist destination system is not disturbed. Maximizing benefits (usually at the cost of excessive visitation) in this case can lead to the devaluation of or irreversible damage to, or even to the complete destruction of, the main tourist attraction—a cultural monument, natural area, or specific object [17].

Previous studies have suggested that the elements of the marketing mix are key variables in the creation of brand equity (for example, ^[8][18][8,18]). More specifically, among these variables advertising and sales promotion emerge as specially interesting. In fact, the investments they gather in comparison with other forms of marketing activities are significantly higher. For example, in Spain in 2018, the estimated true investment in the advertising market stood at EUR 12.83 billion, or 1.06% of GDP [19].

Despite the importance of the respective effect of both advertising and promotions on brand equity, academics stress that more research efforts into the role of such factors is needed [20]. These authors also found distinctive effects of monetary vs. non-monetary promotions on brand equity.

On the other hand, according to ^[21][22][23][21,22,23], social networks have become a key element in the promotion of heritage tourism destinations. These authors focus their studies on the effect that the use of social networks exerts on the generation of the knowledge and awareness of heritage destinations with the aim of attracting tourists. Refs. ^[24][25][24,25] called for further research on the impact that social networks have on the development and competitiveness of the tourist destination and its brand equity.

However, the literature review has revealed that the research on the impact of sales promotions through social networks in terms of the brand equity of a tourism destination in general is scarce [26], and with respect to a destination associated with a heritage site it is even scarcer; thus, more research efforts are required to better understand its effect on the formation of brand equity. In addition, few studies have analyzed this effect on each of the dimensions of brand equity. Ref. [27] showed that social media-based communication activities exert a significant influence on brand image, Ref. [28] found that they are related to brand loyalty, and Ref. [29] found that they rely on awareness. However, these studies do not analyze their effect on a brand of a heritage destination nor differentiate between the type of promotions. A recent study by [30] found a relevant effect of sales promotions on perceived quality in relation to a brand associated with a heritage destination.

2. Cultural Tourism and Heritage Tourism

Ref. [31] (p.4) conceptualized heritage tourism as referring to “travelers seeing or experiencing built heritage, living culture or contemporary arts.” According to [32], cultural tourism would include heritage tourism, artistic and creative tourism, and other forms of culture consumption. In this regard, Ref. [33] defined cultural tourism as a tourism form that is based on the values of the cultural heritage of a destination and transforms them into products that tourists can consume. It is one of the oldest forms of tourist interest, and yet it remains one of the most misunderstood types. Likewise, Refs. ^[31][34][31,34] consider cultural tourism to be essentially a synonym of heritage tourism, which is often described as involving the travelers who visit, experience, or participate in a living culture, art, performance, music, or other component of contemporary culture, motivated by an interest in the historical, artistic, scientific, or heritage offerings of a community, region, or institution. Cultural tourism has not stopped growing, in such a way that in 2017 the cultural tourism market made up more than 39% of international arrivals worldwide [32]. European statistics also show that cultural heritage attractions gather a great deal of interest. According to a report published by [35], cultural tourism represents 40% of overall European tourism activities. The marketing of heritage has also progressed at a good pace, growing thanks to word of mouth, the publication of popular guidebooks, and marketing initiatives designed to “sell” tourist destinations. In this regard, the selection of an activity related to cultural heritage is regarded in a similar way to the intention or decision to purchase a specific brand for a tangible product. Thus, this phenomenon affects the decision-making process of individuals when it comes, for example, to choosing a monument to visit and discarding another. The examination of the behavior in space focuses on the reasons for that apparent action to understand the processes of decision-making, choice, spatial cognition and mapping, acquisition of spatial skills, risk aversion, uncertainty, habits, searching and learning, emotional states, relationships, representations of knowledge, values, and beliefs [36]. Therefore, as suggested by [37], not only countries but also regional areas and cities are competing aggressively to persuade tourists to visit their heritage attractions.

3. Brand Equity and Cultural Tourism

The brand equity concept originated in the 1980s as a key construct in brand management ^[8][11][8,11]. According to ^[11][38][11,38], brand equity has been recognized as the means to differentiate a company’s products and services from its competitors. Brand equity is defined as “a set of assets and liabilities linked to a brand, its name and its symbol that add to, or subtract from, the value provided by a firm’s product or service to its clients” [11]. This multidimensional model differentiates between several assets, notably, brand knowledge (awareness), perceived brand quality, brand associations, brand loyalty, and other assets specific to the brand. In general, studies regarding destination brands consider that the consumer-based brand equity model (CBBE) based on the work developed by ^[11][38][11,38] is the appropriate tool to measure and evaluate the performance of the destination and customer perceptions about the brand associated with the destination ^[9][15][9,15]. With these premises, Ref. [39] developed a five-dimensional brand equity model for a cultural destination on the basis of the BE dimensions defined by ^[11][38][11,38]. According to [39], the assets associated with the cultural destination brand are the cultural assets associated with the destination, such cultural assets having a positive impact on the destination BE, which in turn leads to competitive advantages. In addition, Ref. [40] developed a brand equity model applied to museums. In their study they establish the relationships between the BE dimensions, including the value perceived as a mediator of these relationships. Ref. [13] introduced the concept of cultural brand equity (CBE) and proposed five determining factors that affect the formation of BE in artistic and cultural exhibitions, confirming a positive link between brand equity and visitors’ satisfaction and their willingness to pay. The present study uses a measure of CBBE comprising five dimensions: brand awareness, perceived quality, brand image, brand loyalty, and perceived brand value.

4. Social Media and Heritage Brand Equity

The ability to engage directly with the consumer via social networks provides the organization with an opportunity to heighten brand awareness, recognition, and recall [32]. The “consumers” of the cultural heritage are perceived as active recipients of important messages [41]. The findings of the empirical studies by ^[26][28][26,28] also showed that the implementation of marketing activities via social media is positively related to a greater brand equity and, in particular, to a more favorable brand image. Similarly, other authors demonstrate that the use of social media positively influences brand trust [42] and brand loyalty ^{[28][42][43][44]}[28,42,43,44] through the creation of brand communities, and therefore positively enhances brand equity ^[26][29][26,29]. Ref. [45] suggest that, thanks to the more dynamic, ubiquitous, and immediate interaction they offer, social media can significantly influence the performance and success of a brand. Social media-based marketing actions in general, and communications activities in particular, are likely to affect the generation and maintenance of brand equity [46]. This influence derives from their ability to affect each of the dimensions of the brand equity concept itself (awareness, image, loyalty, perceived quality, and value) ^[38][46][38,46]. In the tourism sector, the results obtained by [47] showed that sharing information about the destination through social networks had a positive effect on destination brand awareness and on the quality of service at the destination. Moreover, their findings indicate that destination brand awareness positively influences tourists’ perceptions of both the quality of service associated with the destination and the destination itself. Some studies on the effect of social media on destination choice decisions suggest that there is a positive link between perceived quality, electronic word of mouth (e-WOM), brand image, and brand performance [48]. More specifically, Ref. [49] examined the impact of social networks on museums’ brand equity and found that there is a link between social networks and the dimensions of brand equity: brand loyalty, perceived quality, brand identity, brand awareness, and value. Ref. [47] note in their study that tourist destination managers should use tools that increase awareness of the destination brand at an optimal level, via both traditional media and social networks. However, these authors point out that social networks should be taken into consideration beyond traditional channels, as they allow faster communication with the target market and are financially much more advantageous by comparison.

5. The Influence of Discounts and Free Gifts Offered via Social Networks on Heritage Brand Equity

Promotion through social media and other digital marketing tools provides a wide range of customer and work in multi-dimensional approach using digital self-promotional tools, products reviews, price-based promotion campaign, loyalty programs, drop-shopping incentives, and reseller promotion [50]. In this regard, several authors have demonstrated that sales promotions on social networks are able to affect destination brand equity [51] and engagement [52]. Sales promotions can generate both hedonic and utilitarian benefits, but the latter are found especially when a monetary incentive is used, whereas the former are more evident when a non-monetary incentive is in place [53]. The academic literature suggests that the hedonic benefits are similar to the emotions experienced by individuals, such as pleasure and self-esteem. As a consequence, it is to be expected that those promotions triggering these types of benefits will be related to feelings and emotions, with the non-monetary ones fostering more and favorable brand associations, thus enhancing brand equity ^[20][54][55][20,54,55]. Brand image refers to the associations that consumers link to a brand [38]. Ref. [27] observed that social media-based communication activities exert a significant influence on brand image. Regarding monetary promotions implemented online, they have a negative impact on brand image ^[54][56][54,56]. Refs. ^[57][58][57,58] defined perceived quality as the consumer’s judgment of the excellence or overall superiority of a product/service relative to the available alternatives. Refs. ^[11][59][11,59] positioned perceived quality as an intangible, general feeling about a brand, and an important element in brand equity generation. Consequently, perceived quality is a subjective evaluation of a particular product or service, with such perceptions potentially differing from one individual to another [60]. Moreover, online monetary promotional campaigns can result in negative perceptions of the brand, mostly due to the fact that they are in place for a relatively short period and lead consumers to think of the price instead of the brand. This phenomenon could negatively affect both perceived quality and brand associations [20]. Turning to loyalty, according to [11], this is a measure of the relationship between the customer and the brand, and it often constitutes the very heart of brand equity. Indeed, such is the importance of loyalty that other measures, such as perceived quality, image, and associations, are based on their ability to influence it [11]. In short, loyalty represents a favorable attitude toward a brand. This loyal attitude is the result of the repeated purchase of the brand over time, during which the consumer learns that the brand can help them make the right decisions regarding the fulfillment of their needs—that is, that the brand enables them to meet their needs ^[61][62][61,62]. The use of social media positively influences brand trust [42] and brand loyalty (^[42][43][42,43]). Refs. ^{[28][42][44][63]}[28,42,44,63] conducted a study in the field of tourism, which confirmed the effect of social media marketing on customer loyalty. On the topic of online promotions, Refs. ^[64][65][64,65] found that these significantly affect loyalty to the destination, and that they provide detailed and relevant information that helps travelers choose certain tourist destinations. These authors hold that a reliable online promotion can encourage potential travelers to make repeat purchases. Regarding cultural heritage, Ref. [66] shows the positive effect of social networks on heritage destination promotion.

The Moderating Effect of Sales Promotion Proneness

There are several studies that show that promotion proneness is one of the primary moderators of consumer response to sales promotions ^[67][68][69][67,68,69]. Consumers who are prone to promotion modify their purchasing behavior to benefit from the temporary incentive offered by the sales promotion. This implies that the consumer’s propensity to take advantage of discounts is a result of their intention—at a cognitive level—to redeem that discount [70]. Various authors suggest that sensitivity to different promotion types may explain the different responses consumers present when exposed to a promotional activity ^[71][72][71,72]. Those consumers who are more promotion prone will display more interest and greater motivation to process them. Refs. ^[72][73][74][72,73,74] concluded that promotion-prone consumers are the most “expert” buyers of all, as they appear to evaluate the benefits of the promotion and integrate them into the information they process for the purpose of decision-making. Other authors, however, claim that it is precisely promotion-prone individuals who process such information via the peripheral route, as they are willing to judge an offer as appealing solely on the basis of promotional signals [75]. According to [76], promotion proneness is negatively correlated with the need for cognition, such that more prone individuals will present less information processing, and the mere fact of the existence of the promotion will be sufficient reason to acquire the product in question. Thus, promotion proneness moderates the effect of social-network sales-promotion type on the variables of brand equity (brand awareness, brand image, perceived brand quality, brand loyalty, and brand value), affecting the way in which consumers process the promotional stimulus and the capacity of the promotion to motivate the user to process it.