زمانی که مصرف کنندگان مادی گرا به سیستم های اشتراک گذاری تجاری می پیوندند  When do materialistic consumers join commercial sharing systems

1. Introduction A growing number of consumers consider commercial sharing systems (CSS) a viable alternative to product ownership (Belk, 2007; Botsman & Rogers, 2010; Havas, 2014) that competes with the dominant logic of purchasing goods (Belk, 2010; Economist, 2013; Sacks, 2011). The commercial sharing market has an estimated volume of more than US$100 billion (Sacks, 2011) with the potential to exceed $335 billion by 2025 (PwC, 2014). The global car sharing revenue alone will grow to $6.2 billion by 2020 (Navigant Research, 2013). Accordingly, marketing academics started to explore the drivers of sharing participation to develop attractive sharing offerings. Yet, consumer research is still in its early phase (Belk, 2010, 2014). The current literature demonstrates that some consumers join CSS due to financial restrictions and a tendency toward frugality, while others participate for ideological reasons (Botsman & Rogers, 2010; Lamberton & Rose, 2012; Ozanne & Ballantine, 2010). In order to expand the share economy to a broader mass of consumers, marketers require knowledge about the motivating factors in different consumer segments, particularly for consumers who have been reluctant to make use of CSS so far. As materialistic consumers prefer to buy and thus own goods (Belk, 1984, 1985), there is reason to expect that consumer materialism (the deep-seated wish to possess things) is the key barrier to join CSS. The present research proposes that, under certain conditions, even materialistic consumers may choose CSS-offers. Yet, their motivational drivers may differ from those of frugal or sustainability-conscious consumers (Geiger-Oneto, Gelb, Walker, & Hess, 2013; Hudders, Pandelaere, & Vyncke, 2013; Wang & Griskevicius, 2014). This research suggests that the desire for unique consumer products is a potential moderating factor. Consumers with a strong wish to use unique products may join CSS despite materialistic dispositions. Although no empirical evidence of the interplay between materialism and the desire for unique consumer products has been published, recent studies provide indications that both concepts relate to sharing intentions (Lynn & Harris, 1997; Ozanne & Ballantine, 2010; Podoshen & Andrzejewski, 2012). This research makes several contributions to the literature. Study 1 tests two types of materialism (possessiveness and non-generosity) against a set of factors that potentially shape the intention to participate in CSS. Study 2 then analyzes how the desire for unique products attenuates the detrimental influence of materialism on sharing participation. Study 3 finally shows how the interplay between both factors depends on whether the ownership of one product fulfills the basic product category need. Together, this research has theoretical implications for explaining consumer sharing behavior as well as managerial implications for developing new sharing offers and for widening the sharing market.