I can think of a few reasons..when you're banned from a forum, the natural urge (at least for some, is to think "they can't do that to me!") and there's nothing you want more than to bust right back in. That's one of the things that drives me back to enotalone.com over a HUNDRED times...that and my OCD. It's not healthy but it's a damn good example for ya..LOL
Then there are gamers who are caught cheating on some online internet gaming boards..they are banned, and they come right back.
Still others post stuff on YouTube that is against the TOS, they get banned but they still want to view movies...they're IP banned so they can't even load the website in their browser without using a proxy.
You get the idea..
yep....