Yes it is definitely only possible for small gamblers to use casino sites without kyc. Because without kyc very big transaction limit is not given which is why KYC is mandatory for big gamblers and big amount transactions and bets.  And if they don't do KYC any time they may face problem and in that case their money will be at risk. So big gamblers must kyc because if they Don't do that. it will put their money at high risk