then you havent looked
https://www.filmstories.co.uk/features/how-psycho-revolutionised-cinema-start-times/
“then you haven’t looked [into the movie start time history]”
You said “there used to be no start times”.
Fact is, Hitchcock, for Psycho, ruled that no one could come in after the film started.
Theaters have always announced the start times of their movies. Rummy would not look well upon your inaccuracy.