IMO, politeness should also take account norms that make the other party feel the most comfortable (within reason of course). It took me a long time to learn t

IMO, politeness should also take account norms that make the other party feel the most comfortable (within reason of course). It took me a long time to learn that when your friend's dad tells you 'Please just call me John', continuing to address him as 'Mr. Smith' is less polite, not more. Same thing with money.