Check out the recent controversy over Activision and Call of Duty. Evidently the game code requires access to your webcam and the company has patents on using your gameplay to train a bot that play like you do, then uses the idle time to make the bot play while you are away. This bulks up the pool of players ensuring you are matched with people resulting in a good experience for you. There's also a patent detecting your emotional state while you view their in game store, possibly for adjusting price to influence you to buy or spend more.