So I came up with another way of dealing with no-shows. Please let me know what you think of it:
Starting with the next Wall Street Poker season, I propose to take a $30 deposit from each player on their first tournament of the season. This $30 would go into a special escrow account (the Wall Street Poker cash box) and would be used as a financial incentive to get people to come to the games. If a person happens to forget about a game or cancel at the last minute without a valid reason, $10 would be take from that person's escrow account and added to the prize pool for the tournament they were going to be in. The $10 would at least partially offset the fact that they weren't there.
When a person's escrow account reaches $0, they forfeit invitation privileges until they fill up their account again. Arrangements could be made to fill up the account via check or Paypal, if so desired. At the end of the season, all escrow balances would be refunded to the players.
What do you think? I think this provides a nice balance of punitive financial damages, while at the same time allowing people to buy back in if they don't show up enough. Also, it is easy to administer from my side.