I've found a quilt of mine "for sale" on a spam selling site. I like to share photos of quilts on here, but from now one I'm going to put a water mark on my quilt photos. It won't stop spammers, but it will hopefully stop some oblivious person from being taken advantage of and buying a quilt for $50, only to never get it.
Yes, once something is on the internet, it's out there forever.