They aren’t good Christians then, and if Christian social shame was still the dominant flavor of social shame we may not see such egregious behavior (not arguing there would be perfection, of course).
You say Christian social shame, those are the very first things that come to mind.
The modern western morality is different from Christianity in a lot of ways. So, yes, a person executing classical Christian morality would shame for those things and consider them wrong. I’m an atheist so I don’t have to agree with them, and I didn’t make their rules, that’s just what they are.
I’m also not claiming that Christianity enforcing a morality would make better “people”. It would just make better (i.e. more consistent and less hypocritical) “Christians”.
Christian morality includes “don’t be selfish” as a high ranking rule.
Being selfish is against the religion, therefore selfish Christians are not implementing Christianity properly, or in other words they are being “bad Christians”.
I don’t think of morality as one thing, I’m not claiming Christians or well functioning Christians are “more moral” because that is a nonsensical framing. It would be like saying that frogs are “more animal” than goats. No, they are just different animals.
So is a Christian also allowed to own a profitable business? Isn't that pretty selfish, instead of making only the minimum and using the rest to help the needy?
Or is a profitable business OK, but raising prices by more than inflation isn't?
Or can a Christian run a factory that dumps runoff straight into a river?
"Being selfish" is itself poorly defined. The Bible is not much use - when it's not contradicting itself, it's vague.
Christian morality is not one single thing, hence my "no true Scotsman" comment.
So yes, it could be the case that the flavor of selfishness we are discussing is on the border and would be debatable. But if the sort of people you are referring to are the same sort of people I’m thinking of, I don’t think most Christians from say 1850 would accept them as Christians. The social bar for calling oneself Christian in current year is practically nonexistent. This is different from no true Scotsman.