For someone not involved in either the movie tv or music industry I’ve oddly met an insane number of celebrities and artists not to mention some of most wealthy and powerful politicians and individuals in the world in random almost Gumpian social situations.
I can assure you that for the most part this is entirely true (I have met two that were either rude or maybe having an off day.) If you can forget for a moment that you’ve seen them on tv or in concert and treat them like anyone else they reciprocated in kind.
Of course it helps that I’m a bit face blind occasionally and more than a few times have gotten a chuckle from someone very famous that I should have recognized when I asked “and what do you do?”