In those kinds of games where you play against different players, and your main objective is to defeat your opponent and claim the winning prize. Then this is why the house or the casino will take a cut from the winner, which is called a rake. This is usually taken in the poker games that happen in the casino. Another thing is that the casino gives complimentary items to most of the users because they might be newcomers or they are regular to the casino and are done as a gift. You can learn about it on nebraskahistory.org.