I used a code one time for a game I didn't own but it was from a list of unlabeled/surprise codes that people had replied they had gotten Fable III stuff from (I do own Fable III). When I reedeemed one and it was for a Kinect game, and I don't even own a kinect, I felt like crap about it. I still feel bad, but there was no way of knowing! Feels good to get that off my chest, I felt like such an unintentional jerk.