If you guys care about privacy while gambling better re-think before you make a deposit. below you can find a list of casinos which ask/ don't ask for KYC after winning big amounts
I agree with you here.If a casino enforces doing KYC after winning a good amount of money,they should be doing the same before money is being deposited on the account.This is a small gimmick every low graded untrustworthy casino will perform to steal from players as they know people are hesitant towards submitting documents online especially if gambling is not legal in their jurisdiction.
After KYC,there is another gimmick called "Security Procedures" which kinda works the same way.