By means of an ethnographic approach, this research examines perceptions of fairness and consumer behavior in an emerging non-monetary sharing system. In contrast to market exchanges, which are defined by clear rules and principles of reciprocity, the redistribution of goods in a "sharing" context is in many cases less institutionalized and thus open to contestation. We draw on concepts from institutional theory to map out the interplay of different and partly contradicting fairness perceptions in an emerging non-monetary sharing system and explain how those are negotiated and synthesized. We explicitly highlight a non-relational fairness principle, leading to the stabilization of the sharing system under study through processes of "goal sharing" and "hierarchical coupling". We discuss our findings in terms of their implications on sharing theory and the role of fairness within this literature stream.