I take table selection quite seriously and there's a number of players I don't want to have position on me. The way I deal with this is that if a player I don't want sits down I'll play until he's paid in or until I win a hand before leaving. It's not technically hit and running but the idea is to make money... not to give it to better players. At the end of the day though, if people want to hit and run, it's their choice. Remember that there used to be a rule against check-raising, would we want to go back to that much regulation.