interesting fact: chilistakes using btc mixer for both deposit and withdraw. They immediately transfer money you deposited from their address to the mixer. Usually casino using their own wallet, maybe a few but never saw crypto mixer.
That's definitely a huge red flag to be honest. I mean why would a site that has nothing to hide do something like this. There can only be the issue of tax evasion (maybe) or something like money laundering that would make a site taking these kind of strange approaches. Makes absolutely no sense to do this if you are a reputable business and and don't have some sort of backup agenda ( rug pull ) or similar.