Casinos often offer "free play" instead of cash for a prize because it encourages the winner to continue playing in the casino. When a player receives "free play," they are more likely to stay in the casino and use the credit to play additional games, which increases the casino's revenue.

Well to start off, FreePlay is basically defined as credit to play in a slot machine for free in order to win real money. Anything you make off of the FreePlay, is yours to keep...or play with.