I'm guessing the person in question must have had a very bad experience, and isn't willing to have it repeated. When it gets right down to it, there's nothing you can do if someone rips off your stuff. Unless you're really willing to spend huge money on lawyers and courtcases. I've been in the position three times now, and as a result I don't even like photographs of my 'real life' 3d work appearing in magazines, because assholes immediately copy the ideas. I've walked into a pub and found casts from my work ranged around the whole of the main bar :o( Pub manager said "not my problem, I paid a company to do it". Architect said "not my problem, I bought them from a workshop". Workshop guy said "I don't care, f**ck off".