> "Not too long ago, it was perfectly fine for people to turn up at your house unannounced, to pay you a visit, for no reason in particular other than to engage socially and you were expected to host them at your house (!)."
That very much differs with social class and location. See https://en.wikipedia.org/wiki/Visiting_card for the elaborate social conventions which developed amongst the European and American aristocracy regarding visits to the home.