Yeah I’ve been to my cinema a ton and every movie I’ve ever been to they leave the lights dimmed until the credits finish (basically lights off during movie, dimmed during credits, fully on after). They’ll also wait until everyone has left until they start cleaning.

This one they immediately turned the lights on fully (even before the first after credits scene that is almost instantly) and came in to start cleaning up, because it was so much worse than normal they needed that extra time.