There are "provably fair" schemes where casino reveals a hash of the outcome before players bet.
They explained that some games were rigged but still had to give [big] prizes to someone to keep the show going. Some would organize events and send their big players on trips.
Like an open secret no one talked about. The system is this: For a good while keep depositing more money into the account than spend and leave all the winnings. If they are cheating such account will win incremental amounts. Cheating or not they need to show their players are real people periodically so they organize VIP events and send the top players.
When asked if their winnings were real they examine the poker faces around them for a while until one said that it was irrelevant. I wont cash out either way!