Some don't like to submit KYC since they want to protect their identity. They can't afford to expose their details because some maybe a well known guy or maybe they are also don't want to get any possible problem regarding on hacking or any related on financial issues which might happen to them if they don't became more careful to give their personal details to anyone. We can't force people to just accept this KYC thing since its still up for those people if they want to continue or just quit if KYC will be implemented to all casino exist in this forum.
This KYC topic has always been a debatable one as some are comfortable with it but others don't like to submit any documents to protect their privacy and remain anonymous which is why they have selected crypto casinos.But the thing is simple if you are not comfortable with it find other options as there are available otherwise you will have to comply with the regulations of casinos if you want to withdraw funds.