DR FJL - I think mentioned the length of a play vs. the length of a movie and the possibility of having to go to the restroom......
If you have to get up during a movie, it disrupts the people around you - but if you have to get up during a live performance, it disrupts the people on the stage and you become part of the performance.....
At least that's the difference for me.....and when someone goes out during a play or musical.....you just know sooner or later that person is going to come back in and go through the whole process in reverse.....