5. Not reading or not caring about BitBet's FAQ and the open, fully explained, warnings about the rare potential for this very situation on this very forum;

This policy is ridiculous and can't possibly be legal.
If I try to put down a thousand dollars on a roulette table after the guy waves his hand, the bet is rejected and I get my thousand bucks back. The dealer doesn't stuff it in his pocket and call me a fag.
Either you accept a bet, or you don't. If you accept it and they lose, you get to keep the money. If you accept it and they win, they get more money. If you don't accept it, YOU DON'T GET TO KEEP THE MONEY.
Scumbag shit at its finest. I don't care how many times you've been defrauded by somebody double-spending, you don't get to make up for it by fucking stealing from people.
EDIT: Looked into this some more, and holy shit! These people are RAKING IN stolen money from bad bets. As per the FAQ, they consider them "gracious donations" to their investors. In March they stole 23 BTC, and April they stole almost 26.
Fuck these people with a red hot iron. Someone else in here posted a whois of the website, the owner needs to be put in cuffs for grand larceny.

Well when I said that of BoB I'm assuming that someone that runs the site has access to all the private keys of all the address and the database that states which address belongs to which user; and that such person is willing to do all the verification and sign a message with the involved address stating it belongs to person x and that it should be refunded to address z. Other than lack of willingness I don't see why it couldn't be done.