My local pool hall has free practice before the tourneys, and after you are knocked out, you can play free until the tourney is over. I believe that is more than fair. Ive seen people play the tourney and go 2 and out in less than an hour, so if you make them pay from that point on, they will just leave. If you let em stay, they order food, sodas, snacks, beer, etc. It really makes a good impression on new players when they find out they get to play for a couple more hours after they get put out. If a lower skill player gets put out early, he/she might be discouraged to enter another tourney, which is bad for our local pool scene, because we need all the pool players we can get!
Joe
Joe