Lest anyone doubt that good players take money from bad players, one relevant academic study reaching that conclusion is described here. Would anyone request a similar study for bridge, where the long-run triumph of skill over luck is obvious?
I wonder what other common recreation pastimes could sneak out from under anti-gaming rulkes based on similar reasoning. Craps, I would assume, is mostly luck (setting aside the skill involed in breaking rigged dice into the game, or avoiding stupid bets.) Betting on horses clearly takes skill but... an efficient markets argument would be that in poker there is a profit opportunity for whover is the best player at a (relatively small) table. In parimutel horse betting, shrewd players from all over the world have a chance to participate.