Even if you do find the cabinet in the lavatory, the probability calculations for a simple use case are ridiculously complicated. It does reek a bit of "minimum compliance required by law."
On the plus side, Hoyo (at least in Star Rail) doesn't bombard the player in-game with pop-ups or the like. A zero-spend player that just wants to poke around in the story or the game world isn't going to be harassed. Instead, it's earnest marketing, by way of letting the player use characters on trial, featuring them in the story, or high-quality video productions published outside the game. They make as much money as they do because their production values on that stuff are among the best in the business.
As far as running a digital goods casino (where you don't own the goods), I've seen far worse. I still don't think we're doing as much as we should to protect those with addictions to gambling or FOMO from these products, however.