Signing up for their player's clubs will get you some free stuff, even if you never play any of the table games or their slots. That's the most free stuff you'll ever get from any casino, beyond that it's going to cost you.
Gamble in a specific casino frequently.\n\n The more frequently you visit a single casino, the more the staff will start to recognize you. If the pit boss or host know you as someone who gambles a lot, they will be more likely to come up to you and give you perks like a free room.