Inequity aversion is a pretty classic part of game theory and experimental economics. Some of the earliest experiments included the ultimatum game, where one of two parties gets to decide how a sum of money is split, but the other has veto rights (in a veto, neither gets any money.) A purely rational person would always accept a non-zero deal, since they would get a little money rather than no money. But most people (myself included) are likely to reject a deal that’s “too unfair” to punish the other player.
