Yes, it happens to every gambler who spends a lot of money. That is how VIP tiers are defined, based on how much you spend. There is no way for them (or anyone) to understand the customer's state of mind. Should it be illegal for retailers to offer customers discounts? Compulsive shopping is significantly more common than gambling addiction, do retailers target those customers?
If you never want to gamble, you tell the state regulator you never want to gamble and you will be unable to use any site.
Maybe not their state of mind but if you have access to people's betting history you can very likely identify people who are "problem gamblers", especially if you also ask them their annual income when they become a customer (I have no idea whether they do this in the US, but they do on UK sites and will suspend your account if your betting exceeds certain thresholds).
You certainly wouldn't even AI to spot people who are chasing their losses for example.
As to whether they should be obliged to care, I'm not sure. But through public policy you can make it their problem.