Places here in our province are so strict the reason why the people are really following the procedures, they are even requiring now people to wear face shields. Strict protocols might decrease their increasing cases, though this is still a casino, bars are available here so there are a lot of people influenced by alcohol, not following rules is really inevitable at these places.
Face shields are ok and highly recommended but that doesn't guaranty that you are 100% safe because we are against an invisible enemy so this kind of case in court will not have a chance because people will have a hard time proving where they contacted the virus, is it really in the casinos or when they are travelling or a store, there is no exact place to pin point.
I guess that is why it falls to the hands of the people to keep theirselves safe.
Face masks and Face shields can protect us from being contaminated, wearing those could protect us but we can't say that these casinos are wanting to take those off for them to sue these casinos, right? It falls all over to that people is he/she disinfect his/her face shield and face mask when they go home. It is not the fault of the casinos if we will be basing that to what you've said.