all the players playing 10/20 NL are top players. how can they all win?
If you ever watched one of these games, you would quickly realize that this is not true.

Even if it were, obviously the good regulars have an edge on the bad regulars. You'll also get the occasional rich fish that wants to gamble, the guy that puts his last $1257.21 on the table hoping to get out of debt, and the frequent 2/4 3/6 5/10 grinder that has a big bankroll but is -EV at 10/20 or higher.