Well from what i have been told talking to a few breeders and keepers is as babies, they will bite if given the chance. As they mature, they tend to mellow out. But overall it depends on how much you interact with them. I was told to start working with them with 1 glove on the hand near the bitey part and a free hand holding the tail part. Steve Angeli has pics of his girlfriend and kids holding some large ones and he told me his girlfriend isnt really into reptiles.

And yes, people breed them. It is illegal to collect them in the wild. And certain ones are actually endangered.