If the game is sealed, you may actually be able to trade it into Kmart.
Also, I question the retail fraud aspects of this. Intent goes along way to the fraud, he isn't trying to make money off of anyone, he's just trying to get the game he actually wants. If it isn't fraud if she bought the game he wanted at Kmart originally, why is it fraud if he takes it back to Kmart, and gets the right game, there is no harm
Secondly, are you sure Best Buy stopped supporting the site because of retail fraud topics? If you are sure, fine. But, Best Buy went on the public record in the last few weeks of not wanting certain types of cheap customers. They don't want customers who come in and buy there cheap items, if they aren't going to buy other stuff too (big articles carried in the Wall Street Journal and the AP). This site seems to cater to the exact kind of person that they are now on record of not wanting in there store, so that could be why they dropped there advertisement on the site.