With bitcoin gambling there is no need for kyc for online casino's. Its advantage is that countries where gambling is not allowed can can take part in gambling while the down side is teens under 18 can also take part in such online gambling platforms. It's just a double edge sword IMO.
I'm surprised you can say this, I think you're not a regular gambler since you never faced the casino ask your KYC. It's true upon registration you don't need to submit KYC, but you should check their terms of service to know if the casino is really no KYC or KYCless. KYCless is the casino ask your KYC when they feel you doing suspicious activity on your account. But in some case, the casino ask to random gamblers even though they didn't do anything harm.