Ben is getting a little tired of Pawnee, but he’s only two stamps away from his “free” meatball sub. Unfortunately, his card is expired. He’s a bit sad about it, but those stamps are essentially a sunk cost. The card itself is a good example of ways that firms price discriminate and offer discounts to bulk shoppers.
See more: free lunch,NSTAFL, opportunity costs, price discrimination, second degree price discrimination, sunk costs