Play the white man

"we do still find it odd that people eat horses, snails and frogs and use 'motherfucker' as a term of endearment - polite society in Mayfair would be mortified to hear such a word."

I have to guess you are talking about several cultures across one or more nations here.

Certainly MF is frowned upon in polite society everywhere I know of. I don't believe it is often used as an endearment.