I see them quite often on SF craigslist, and they are usually between 1-3 years old and normals. Like the others have said, I believe it's a combination of two things - getting over the novelty of snake ownership, and uncontrollable changes in one's situation. For example, one guy trying to sell his right now is being deployed... not much he can do about that, although I guess you could say "why did he get a snake knowing he's in the military?" But for all we know he just joined up, so I try not to judge!
Unfortunately that's a rare example, however, and most simply don't want to bother anymore. I love the ones who say "I'm moving" or "I don't have the space and/or time for them." Puuuuulease.

BPs are very easy to care for (if you just have them as a pet), take up little space, and unless you're moving overseas it's unlikely he/she couldn't come along. I used to volunteer at a cat rescue, and it was the same old story... I wish those people would at least be honest, and admit they don't want the responsibility anymore. I think we've all had to re-home a pet at one time or another, but treating them like disposable possessions is NOT cool.
