Why do people care this much about completely harmless and inconsequential things other people do? I've personally never given a shit when someone else claps when a plane lands, same with people clapping in movie theatres. The world is miserable enough, let people enjoy the little things, it's not like they're forcing you to clap with them.
Precisely because they are harmless and inconsequential. Complaining about things like this or pineapple on pizza are just meme complaints. Nobody cares that much about it in reality.
What I've never understood- it doesn't bother me but I've never understood it- is people who clap after a movie. I don't mean people at the premiere where the filmmakers and actors are, I mean people in some town in Wisconsin or whatever. It's weird.
It's for the projectionist, and it's probably outdated these days. But until digital film distribution became common it was actually a fairly involved job.
Edit: and if you go back to the silent film era the scores used to be played live. So maybe it's even a holdover from that.
Interesting theory but if it was clapping for the protectionist then they'd do it at the end of every movie that was well-projected, not just the movies they thought were great.
I feel it's more a habit carried over from live theater and music performances. They're happy and just instinctively clap even if it's pointless as a gesture towards the production. It just an expression of enjoyment they've developed sitting in a theater.