There's a saying among casino gamblers that there's no such thing as a free lunch, except at the buffet. Casinos spend hundreds of millions of dollars every year giving away “comps” — complimentary drinks, meals, hotel rooms, tickets to shows, and even free plays on slots and table games — to their loyal customers. In fact, those incentives often are the key to keeping customers loyal. It isn't hard to get your share of comps, but you do have to know how to go about it.