I have had some bad experiences with school groups who did not know how to behave in a theatre - mostly Shakespeare plays because of where I lived. Some were enjoying them but were not used to keeping quiet. Some just did not want to be there.
Sitting quietly to watch a show is pretty recent. Even classical performances were louder with praise and en-core requests shouted out loud.
I'm not exactly sure when the 'sit down, shut up, and listen' happened, but yeah.