The Federal Trade Commission (FTC) filed a suit in 2014 against Apple Google and Amazon. Although a settlement was reached with both Apple and Google the FTC sued Amazon. All three require a password for in-app purchases or an opt-in to enable purchases without a password.
District Judge John Coughenour in Washington State stated “The millions of dollars billed to Amazon customers without a mechanism for consent, the thousands of customers complaining about unauthorized charges, and the time spent seeking refunds for those charges, all demonstrate substantial injury, it is Amazon’s stated policy that in-app purchases are final and nonrefundable, likely discouraging much of its customer base from attempting to seek refunds.” Apple agreed to refund customers at least $32.5m and Google $19m in unauthorized charges.