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The purpose of the present study was to determine whether providing shoppers with a gift upon entering a store would result in an increase in sales. An experiment was conducted in a pharmacy and a total of 200 subjects were used. The results showed that shoppers given a key chain and thanked for patronizing the store spent significantly more than a control group of shoppers who were not given any gift upon entry ($10.76 vs. $9.21). The results of this study are explained by reference to the literature on reciprocity and gift-giving.
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Friedman et al. (1990) studied this question.
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