Hi there
I have been playing some time now on justbit.io. Won some money, and my account stands approx 8 mbtc. I asked to withdraw 5 mbtc and today they asked me for KYC procedure (ID and other stuff). By their site states explicitly that they do not ask for KYC if crypto was used to deposit. Update: They confiscated today all my winnings without any other notice, nor waiting for me to send them the documents.
Well, I don't think you read the terms and conditions of this casino properly, or maybe you didn't understand some part well.
Based on what I understand, though the site and the customer care stated that crypto players are not required to pass kyc verification, but from other part of the term and conditions, there is a chance that a user that deposited and played through crypto would be asked to submit his or her kyc documents if the casinos suspects anything not right..
So clearly, the casino probably think you are a cheater and that's why they are asking you to submit your kyc document, this also explains why they rushed to confiscate your winning as you are hesitating to submit the documents the requested.