[smnplk]

A hobby poker player here.

The main goal of any poker game is to win money. You win money from your opponents, you don't play agains the house. Although , the house (poker site) does take a small percentage of every pot you win, this is called rake. Do note, that in some games, rake can be so high that it is not profitable to play the game even if you are much better than your opponents. The only way to win money on the long run in poker is to be better than your opponents, so you need to look for bad opponents, it is a well know strategy called table selection or "bum hunting" :)

Nowdays it is still very feasible to make a living off poker, but you will have better chance finding bad player in live games.