This is another bone of contention. Although It is a nice question you have asked because this would help checkmate activities of underage gamblers onboard the casino. In some nation's, underage gambling is prohibited and their is likely penalty for both defaulters including the casino and the underage gambler if caught up in the act while in some nation's their is no law holding anyone to gamble.

I think this question you have asked does not bother with the casino since it  has clearly stated it that there is no KYC which means the casino is free for all to gamble. What you should be think us the local laws of various nation's pertaining to gamble and the age limit for gambling. Each country has its own law as regards that aspect of entertainment when it comes to casino. It is left for every individual to know the right thing to do when gambling from their various locations.