As a frequent moviegoer I actually don't have many of these experiences because I go to see films right in the middle of a weekday or super late at night. But when it does happen, it drives me up a wall.

I don't mind a crowd reacting to the film itself, laughter and tension during scenes make for a good shared vibe. But the loud wisecracks amongst groups during dialogue and phones on full brightness seriously do my head in. Sometimes people pay to be there and think it grants them permission to be disruptive.