When I saw The Others, not only did a woman's cell-phone ring, and not only did she answer it, but she actually started a conversation and then bitched when an usher came and told her she would have to hang up or leave.

And on a number of occassions, I've seen a person politely ask someone to be quiet only to have the people complain (more loudly than when they were talking before) about the gall of the person telling them to be quiet.

It's one of the reasons I go mostly to the Arclight. The crowds there are usually good about respecting the rules of the theater.