To be specific, credit card companies put the bulk of the risk on the merchant. If someone steals your card and buys a book, the credit card company will reimburse you and (most likely) not pay the bookstore. They set up the incentives this way because customers are more likely to use their card when they are protected, but stores can't afford not to accept credit cards.
Which is paid by everyone, even people that settle their transaction in case. I use a cash-back credit-card and effectively my fellow shoppers are subsidising my purchases, because we're all collectively paying the card fees which I'm getting a rev-share on. CCs are a deeply weird model.
