This article follows some of Marcel Mauss's insights to discuss the coexistence of the distinctive logics of gift relations and commodity relations in brazilian society. The analysis is based on field research developed in Curitiba (Paraná, Brazil) which focused the conflicts that arise between consumers and suppliers in the market-place. The evidence points out that the establishment of some sort of equivalence between the transactors as subjects is as important in commodity relations as it is recognised to be in gift relations, affecting even the claims concerning consumer rights presented to state agencies. In more general terms, the article suggests that pacific transactions and conflicts in the market-place might be understood as part of the same communication system, in which the general principle of reciprocity encompasses the instrumental dimension of commodity relations.