Green stamps are reward coupons that the Question Box moderator uses to belittle an Anglican priest who has converted to Catholicism by suggesting the Anglican had it wrong to begin with and that, at Last Day, his stamp book will have been determined to have been filled with the wrong brand of stamps and thus no admittance to Heaven (Saint Fidgeta and Other Parodies, 43).
Trading stamps are small paper coupons given to customers by merchants in loyalty marketing programs. Like the similarly-issued retailer coupons, these stamps only had a minimal cash value 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.
S&H Green Stamps were trading stamps popular in the United States from the 1930s until the late 1980s. During the 1960s, the company promoted its rewards catalog as being the largest publication in the United States and boasted that it issued three times as many stamps as the U.S. Postal Service.