Xor started Graal at 5.21.2010 and a hat was sold at 5.26.2010, so he was able to buy it. But Azrael who started Graal at 5.28.2010 couldn´t have bought that hat because he started when the hat have been removed again. When we would bring the "Old hats resell" into the game it should be made that the players can rebuy all hat´s which where released since they started the game. Older hats (on players view) cant be bought by them. That "auction" should be only like 1 day or whatever.
Still don´t like the idea but could be a good resolution for both sides.

PS: Xor and Azrael where just examples to make it easier to understand.