If you like to look for free Xbox 360 game demos via Xbox.com on a browser, it’s easy to make a mistake that causes you to accidentally buy the product rather than just test it out.
Giant Bomb describes the glitch:
If you’re logged out of Xbox.com right now and click on “Try Demo,” of, say, Fruit Ninja Kinect, you’re then presented with a login screen. After typing in your Windows Live ID information, the bubbly Avatar appears. Soon, a pop-up window shows up, displaying a confirmation page to make sure everything’s a-okay.
In the process of logging in, however, Xbox.com will mysteriously switch from “Try Demo” to “Buy Game.” One costs money, the other doesn’t. It’s reasonable to wonder why one would just click “Confirm Purchase” without careful reading, except that “Confirm Purchase” is the same button that shows up when you want to download a trial version, too. “Confirm Purchase” is the generic term used on the site when approving a download in all cases.
If you click on “confirm purchase,” you’re actually buying the full game rather than getting the demo. A Microsoft spokesperson says the company is “actively working to resolve” the issue.
Xbox.com issue causes risk of accidental purchases [Giant Bomb via Joystiq]