Art thieves

I see all these posts and journals about art thieves and I have got to wonder, why? Why jack someone elses art when you're going to get caught. And not even by one person but by a crap load of people. And then when you get confronted, why be rude and act like you have a foot to stand on? It makes no sense to me. And the thing that amuses me most is that I've seen the stolen art before with a watermark. A WATERMARK. You can't argue the art's yours when it clearly says on there whose it is you pretentious prick! Just take it down and stop stealing talent.