So I think there is no worry for rich gamblers to enter this gambling, just with KYC which is easier.
I think other casinos that want their customers to fill out complicated KYC like selfies on the side of the road or near a red light, that's such an unreasonable excuse and it's likely that the casino just wants to find reasons to deny customers KYC in contrast to Rollbit which has easier KYC to do.
If you have checked about big whales on Rollbit then some players have wagered unexpected amounts like the highest level in past for Rollbit Boss was in million and billion dollars and it was crossed by gamblers but still not required to do such KYC probably from Rollbit side and have payed them huge bonuses also.