KYC is for (according to google):
The objective of KYC guidelines is to prevent banks from being used, by criminal elements for money laundering activities. It also enables banks to understand its customers and their financial dealings to serve them better and manage its risks prudently.
Dont understand why a crypto casino would require KYC from users tho
Gambling regulations. There are a few other reasons to use the procedure - don't assume that definitions are exclusively restricted to the first thing that appears.
If you really want to be pedantic about it, you could say that it's a KYC-like procedure.