Then you just end up with the riff-raff who have $50 to blow. Something Awful charges $10 for an account, but there are plenty of moderators who will ban you if you're a shitheel; you then have to pay another $10 to re-activate your account. It works for them, but I think HN is too self-moderating for that to work--imagine if they auto-banned you when your karma dropped below 0, think of the system gaming that would occur to get others banned!