You could say that a payment processor should morally screen their clients in general, but that seems like a stronger and not-so-reasonable statement. They do prohibit certain kinds of businesses, but I think the bar for that is very high and likely related to chargeback concerns and such.
Any consumer driven market is strongly indicative of its consumers morality, people just don't like to admit it.
> Offering a product is not evil or immoral
So weapons-grade uranium, chemical weapons, payday loans, extended car warranties, life insurance, habit-forming painkillers, etc are all fine?
As a society, we have decided that some products are indeed unacceptable / immoral.
Payday loans, while a bad reputation, can truly help someone out in a pinch who has no other options - but often they're not presented to be as abhorrently predatory as they usually are.
Extended car warranties are pushed by the car salesman who tell the consumers that they need it when they almost definitely do not.
Life insurance is actually a wise investment for some, not even sure why you put that on the list.
Pain killers provide an essential service when used properly, the vast majority of consumer don't form a habit, and those that do were almost certainly not told by their doctor or pharmacist the potential addictive nature of the chemicals.
All those products are, in my opinion, completely fine. What's not fine is the often fraudulent advertising required to sell those products. But that's a different discussion.
Offering a product is not evil or immoral. It may be amoral but that's not the same as immoral. Ultimately the market decides what stays and goes except in extraordinary circumstances.