Without going TAAT. but with reference to any CF stories, selfish bill-splitters in restaurants and so on.
I suggest the reason they get away with it is, that dreadful catch-all phrase that English people are so used to trotting out - from my experience, not least my parents and family.
We are told "don't make a fuss," as soon as anything is queried, eg, someone suggests splitting the bill and one lone person who wishes to pay just for their meagre part of the meal is then exhorted - usually by their partner - to smile, cough up and let it go.
I wish I could ban this bloody phrase from the English language.