Trading stamp

Small paper coupons given to customers by merchants in loyalty marketing programs

Trading stamps were small paper stamps given to customers by merchants in loyalty programs in the United States, Canada and the U.K. which predated the modern loyalty card-based and online programs. Like the similarly-issued retailer coupons, these stamps only had a minimal cash value of a few mils individually, but when a customer accumulated a number of them, they could be exchanged with the trading stamp company for premiums, such as toys, personal items, housewares, furniture and appliances. In trading stamp programs in Hong Kong continued to operate.

This keyword could refer to multiple things. Here are some suggestions: