I know stopping stuff like this is impossible. Ebay's usually got people selling them. But seeing them at cons and watching fans get ripped off buying another fan's hardwork is just too infuriating. It's one thing if they're the price of materials, and maybe a little more to help pay for the table. There was one guy selling copies of out of print anime CDs that are superb replicas for five bucks. I just wish it were mentioned though.
Still, there should be someway to curb this. Perhaps having new covers for edits proclaiming what they truly are (free fan works), in a noticable, tough to alter way might help a bit. So many of the ones I see use the works of Coov and others in the cover thread. I also try to inform anyone I see interested discretely.
Any thoughts?