Casino owners are already millionaires, but after releasing their tokens, they are aiming to become billionaires.

Yes, you're right about that. We can only hope for a generous airdrop for the users of this forum.
I would not say that the casino's own token will bring extreme profits through its value alone. It is more like a method of rewarding loyal users, and such things exist outside the crypto ecosystem.
It brings more profit as a feature, and it's a real wonder that not all casinos have implemented it. Obviously, whoever manages Whale.io, understands the business in its entirety.