Something like this already happened with Xbox live. This guy had his credit information saved to his console, and his dog likes to chew on the 360 controller. Somehow while the guy was out or sleeping. The dog by chewing on the controller turned the system on, and proceeded to buy $62.50 (5,000) worth of Microsoft points.
Here is link to an article about it.
http://news.cnet.com/8301-17852_3-10387665-71.html