Jonah Goldberg's G-file today touches on, but doesn't pursue, an interesting point about Bill Bennett's gambling. Since he never gambled the milk money, and never gambled more than he could afford to lose, why isn't this just entertainment? So he stares at a spinning wheel for 3 hours instead of a movie.
The difference between what WJB does, and real gambling, is that they don't expect to win. In fact, Jewish law states that gambling is a form of theft, and refuses to enforce gambling debts on the grounds that the gambler doesn't really expect to lose. But if the gambler doesn't expect to win, then the contract isn't over a bet, but over the entertainment provided. This may sound like a legalistic way of looking at things, but it does capture an important point.
What was WJB's real state of mind? You'd have to ask him. But for a man to gamble that much, and not step over the line by losing the mortgage money once or twice, he must have been pretty stable, and pretty sure he wasn't going to see that money again. I'd certainly be inclined to give him the benefit of the doubt.