What casinos are those, and what's your deposit-withdrawal activity like? Is it very active? Because another user suggested that it wasn't the amount that triggered casinos to request for KYC, but the activity of deposits and withdrawals. But for me, it was probably the amount. Currently, I play Craps only during Sundays, sometimes Saturdays too, sometimes I don't play. So I'm sure it's not the "activity", but I do - deposit then withdraw after playing. I never leave coins in the casino.
That's probably why they wanted KYC.
Casinos usually don't care about deposits/withdrawals when it comes to small amounts(<$100 or something), but they will care if the amounts involved are moderate-large in size in my experience.
In simpler terms, you should be prepared to submit your KYC at any stage in any crypto gambling site just like FIAT sites if the amounts are moderate-large in size.