The beauty of poker is that it does allow poor players to win sometimes, much like a slot machine will allow the people who feed them to win sometimes. If such a machine was designed to always give you back exactly 97 cents every time you put a dollar in it, nobody would ever play the thing. By mixing it up so that you have some small wins here, some large wins there, and just taking the whole dollar the rest of the time, suddenly you have all kinds of people who love to play slots
and make bets with a negative expectation even though it's effectively the same thing in the end.
If these players who feed the poker economy never won hands, they'd stop playing. It's genius, really.