I agree that the hat should be tradeable. I got it on (only one of) my accounts for just that reason. I do not celebrate Christmas (or any other holiday) for personal reasons, and it would make me glad if I could trade, or even give away my hat to someone who was not able to complete the quest last december.
I would also like to give away my 4th of July Pin '07 (that I accidentally got) and my New Years Pin.
Sugar