Yea, I might have a pessimistic view, but I have also seen the worst.

And I already use watermarks very heavily, and post to other art sites where I have accounts on. I still get my art stolen, no credit given. I have seen people wipe out the watermarks (even by just stroking over it with a black brush on the pic, and thus ruining the pic). I have seen my characters stolen and butchered in forum roleplays. I have seen thieves with millions of views and meanwhile I struggle with a few hundred. People just dont care that the art has been stolen, especially if you aren't one of those super popular artists. Thieves might not get far, but they sure go further than I have been able to.