With all the regulations being enforced by every country on crypto, its hard for the casino's to run without the KYC. Governments wants to control the money laundering and they fear that if casino's are not monitored for the KYC, they will be used in terriosts acts or moving money to criminals etc.
Hard doesn't mean impossible, you can check Freebitco.in where this casino doesn't have any complicated rules on their TOS and of course no KYC. The reason why many casinos have mandatory KYC is they're have a license, but the truth is weak gambling license doesn't make anything difference, it will only make the gamblers feel the casino is more serious. In the end all the trustworthiness is depend on the casino, not the license.