The difference becomes less clear when dealing with groups of people, societies. Explaining things to a group of people, that is more often (as an anthropomorphism) like dealing with an insane person.

That's fair enough. I'd stay away from groups of people. Back in the day, they used to write without vowels, so that you could only really read something if you were either exceptionally literate or were being told what it said by a teacher. I say never communicate with more than a handful of people at once, but I suppose that's not possible a lot of the time.