In 1931 Pepsi was almost broke. The Great depression hit it hard, and Coke had most of the duopoly market for soft drinks in the United States. Pepsi tried many things: marketing campaigns, label changes, and more. Then it came up with an idea of selling 12-ounce bottles for .5 cents, which had been the 6-ounce price. Coke could have followed the price per unit down, but it didn't. Total soft drink demand increased, and Pepsi took a larger share of the demand. Why is the equilibrium of this game different from that of a prisoner's dilemma.