Not getting let in to casino for being “too drunk”

Just looking for some insight into why some big London casinos do this. Multiple times now me and my friends haven’t been let into casinos like Empire or Hippodrome because apparently we were too drunk when we clearly were not. Also another time, slightly earlier in the night we were absolutely smashed but were let in so it seems to be an obvious excuse for something else. All casinos do this and we have witnessed them going this to loads of people.

Not really having a go but I just wanted to understand why they do it. Wouldn’t they want more drunk people wasting their ?