I guess this is cultural. Here in Germany, I have never heard of anyone clapping in the cinema except in very special moments - lets say the room is full of Marvel-Geeks and at the end of the movie Nick Fury comes in. Other than that... well, Rocky Horror Picture Show, I guess, but that is a cult-following built on audience participation. You might hear someone slowly clapping at the end of a movie, if it was a REALLY good flick, or sarcastically, if it was abysmal.
I heard you guys have Twitter-Seats in cinemas now? America's a crazy place.
Also, nowerdays, there are no... whatever you call them, the vendors that walk through the cinema during breaks to sell icecream. Maybe they still exist in larger cities, but I haven't seen one in years.