first, with corwin, I saw a special on him that had some footage of him actually stumbling upon animals (I think one was a rattler), so you know he finds at least some of his animals. I would think that taking cb snakes into the wild for footage wouldn't be a good idea because they would easily escape. I could understand why he might need to do it every now and then though, because he's got bills to pay and such, but I don't think he relies on it at all. It might make you think that they are cb because of the way it seems like he just sort of sees them out of no where, but usually once they see something they will start doing the acting. That's just how it works. The only one I know of that does (or did) the "there's a snake, I'm gonna run after it and try to catch it" thing everytime was Steve Erwin.
Stevens....he's gotten bitten by so many venomous snakes. It's just ridiculous. There were two bites (at least) shown on this one special of his, and he only went to the hospital for treatment for one. Then he came back to the same area messed with the same snake again. i don't know if he uses captive specimens for the "wild" filming, and I don't care...either way he's just an idiot that really does not much more than give the hobby a bad name. He's a crocodile hunter wannabe, but without all of the good qualities.
I remember the first episodes of crocodile hunter...those were the best. Now it's too commercialized. I think I even heard that he is planning on doing live shows in vegas or something.