I don't think the first one is actually obvious. An account was set up. It is on Twitch's computers, and it has a password designed to keep me out. Twitch thinks they have allowed in some other person (who's agreed to their licensing agreements, etc). It seems to me that I'd be circumventing their account system using the fact that I happen to control the password recovery mechanism.

I mean this is essentially silly, because almost certainly what has happened (given my weird name that nobody would normally stumble across) is that my email address has become listed in some database and somebody has decided to use it to sign up for services for shady reasons. So I'm not arguing that I couldn't have gotten away with it. Definitely I could have. But I think it is an interesting reflection on these signup systems and how they might interact with the CFAA, that this weird situation can occur.