I think the only movie I ever walked out of was Grease 2.
Of course I snuck in another theater to see something else.
Anyone remember going to see the original Jaws on opening day? We had a single auditorium theater and they over sold the tickets. They had people sitting in the aisles. It would be lawsuit city now a days.
The weirdest thing that has ever happened at the movies for me was when I was a teenager on a double date. Went to see Texas Chainsaw Massacre at the drive in. Well some idiot decides to start a real chainsaw during a scary scene and run around the cars. The girls had a fit, and frankly it scared the dickens out of me too. I thought I would never get the popcorn cleaned out of the Camaro! Poor choice of a date movie, but we didn't have many options back then.