Also I think that they have to report big wins and display it in their balance or annual report. That is why they cant just write «transferred a big win to a no name», as well as from big wins taxes must be paid, that is why report if to authorities.
Lol, so they can't write transfer to person X in their expenditure, but they can freely write taken from X in the revenue column?
How could this be considered even remotely legal, taking money from strangers but KYCing them when they need to be paid?
You are either KYC-free or you request every document before allowing people to deposit, choose one!
I don’t think casinos do this just to block players from winning. From what I’ve seen, most online casinos have it written in their terms, even if it’s not clear, that they can ask for KYC anytime, even if they promote “no KYC.” If it’s a licensed casino, they also need to follow AML (anti-money laundering) rules, and that usually comes up when someone wins a big amount, especially on games from third-party providers.
Those rules don't apply to deposits? Or are AML rules only when you have to pay winnings?

I really want to hear one case of a non-KYC casino that prevented one guy from depositing because of suspicious behaviour, one example!