That patch on ebay has been up since before the accident. If you look at patches from the other flights they have also been up for a few days. I don't think the person who put this up for sale is doing it because they are trying to take advantage of a tragedy. I've got three patches myself and look occasionally to see what they are going for.
One of the e-bay things you posted said the seller was in CA and the other said Germany, and neither seemed to be wreckage debris. I don't deal with e-bay, but it seems to me that these were just some sleazeballs trying to make a profit sans merchandise (and I really wonder about any takers).
I don't want to seem like Pollyanna, but has anyone actually seen someone trying to sell real parts/pieces and why is this being described on TV as if there is a stampede of trophy-hunters? From what I've seen the people in TX have been respectful of these sites.