Most physical casinos are bound by really strict regulations that will likely not allow them to accept anonymous payment methods for AML purposes unless they are situated in a safe haven country.
There is much more value for mainstream online casinos/sportsbooks like Bet365 to accepting BTC though.
Perhaps it is more possible with the use of third party payment service providers. I guess a gambler in a brick and mortar casino could already swipe his Visa or Mastercard Bitcoin or crypto debit card. So it is also very possible that Bitcoin bets will be accepted in the near future but could also be processed in fiat first. So one could place bets in Bitcoin but the amounts to be registered in the casino books are in fiat value. The payout could also be made in Bitcoin.
That makes absolutely no sense.
If you are paying by a bitcoin visa/mastercard then gaming with these funds will already be in fiat and a middleman is simply handling the conversion process for you.
That has zero novelty when it comes to innovation because it can already be done everywhere.
The real innovation will be brick and mortar providers moving online and partnering with online casinos.
That may make no sense to you but that's what's happening right now. We can actually spend our crypto even in shopping centers that do not accept crypto. It is made possible by all these payment providers. So that could also be possible in casinos whether they are online or brick and mortar.
So probably in the near future Bitcoin bets could also be accepted but will go through third party payment providers for Bitcoin to fiat and vice versa conversions.