It's impossible for any player to win in the end or always win when the house has the edge.
Occasionally someone can walk away at the right time after a big win, but it's very difficult.
The people that are making money consistently through gambling are called grinders...it's possible to do in some games like poker when you're able to read people, not against computers where the odds are fixed.
Check out the movie Rounders, you'll love it.
It depends on that players too if they cashout after winning some coin? I guess in the end they will get some profit right? Actually you can read people the movement, face and everything seems suspicious it you can draw a conclusion for everything that you see but it can't be 100% perfect sometimes you will miss some point that make you fail on reading them