I often go to casinos for work and have my food comped. It makes sense for them to comp my food, otherwise I charge it to my corporate card and we bill it back to them. Comping my food means they can feed us at cost rather than retail. They use the same comp system that they use for gamblers. They don’t track what you had or when. It’s just a “comp”.
Usually when I check in they inform me of my comps and explain the restrictions. Typically they comp food only, no alcohol, and you can eat anywhere except their big steakhouse or fancy-pants restaurant. The restriction is imposed through the point of sale machines at each restaurant.
Most every casino/resort has a lounge or bar that serves food and they always comp the bar food because it is cheap. These bars almost always let you order a steak from their big steakhouse if you ask. When they ring it up at the bar instead of at the steakhouse it is flagged as a comped meal.
The second trick is to charge all the alcohol to your room and pay with the company card. The hotel bill only shows the amount and that it was from a restaurant. I then expense this as dinner. They still bill it to the client; the client can’t dictate where we eat. The expense billings we send them are huge and involve hundreds of employees. They just pay.
Food comped. Alcohol expensed.