Casinos don't care. They can hold reserves in any coin they want and most of it is usually self-running with players covering other player wins with their losses. From time to time someone wins big and breaks the bank where the reserves kick in, but in such case the casino can delay your withdrawal. I haven't won something like $100k but I imagine you don't get instant withdrawal with that kind of money.
That should be by choice, running a casino company in the Beer market is not a compulsory act. But it is by choice. And remember bitcoin will still rise again. So you don't have to discourage gamblers in matters like this. Bitcoin has not devalue itself. 1 BTC is still like that but the only thing that has been changed is the exchange with Fiat.
Beer market is the best. It's a popular thing, especially in Germany and Austria.