Based on my experience, and some statements like ToS.

They have the right to ask you (KYC) sometimes without needing to explain the reason or detail, why? it's gambling even you should prepared to provide this data in case you are being asked. IMO, there always have some NDA things example like cheating in Sportbook (If player getting caught) most of the time they will get asked for KYC & block their account & tell them will break some of their term & conditions.

Player will ask, how they are checking the activity ? and somethings like that. Most of the time casino will be refused to answer these question, because potential for NDA things stuff (they don't want the method being leaked) and the player will find a new loophole.

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I believe CG are the site who required you to register using a simple register like (Email & Password), we all know these typical site is centralized-site while in the future some change might be happend and you required to follow these.

Unless, you are betting with decentralzied-platform everything is using a chain.