Hmm...
I'd wager KYC applies either way (anyone placing a bet should be known, not just who ends up winning) and not paying out wins is a clear breach of contract.
So very clearly doubly illegal. First they let any rando gamble, and then they don't pay out wins.
You'd be wrong. I had the great opportunity of figuring out one store I know sets the "removable scanned item without supervisor input" at 3. For a cashier-operated register, mind you. The limitis for the shift lead to override for the cashiers and not for the person standing around the self checkout isle for customers.
And you'd think this meant 3 items on the bill regardless of their amounts. Nope. 3 items.
You can imagine how the rest of the business's operations looked like. I have to say, I'm impressed they somehow just... chug along just fine. A multinational chain in Europe.