I believe there to be a difference between selling a piece won in a contest vs. being gifted a knife.
I've perused the Knives Wanted section in the past, and have sent the members a single or even a handful from their wish list. If I saw those for sale...that would kinda suck.
There was a member that won a one off piece and had it in the For Sale section the same week. I sent him a check for it. He felt bad, said he needed the money for his family. Was embarrassed about the situation, despite my encouragement that there were no issues, he never posted again.
We all know peeps want to win in a giveaway, but the reasons behind them entering the contest can have little to do with keeping the actual knife. Many look at is as a way to win and make a quick buck. I guess the way I see it is the knife eventually ended up in someones hands who really wanted it.