I work in a cinema, and I approve of this message.
However I really don't care for customers who stay until the end of the credits. You know what if you REALLY want to know where it was filmed or what kind of lenses they used then look it up online when you get home. I've got 5 minutes to clear up all the popcorn, sweet wrappers, coffee cups, and used tissues that people leave on the floor with a broken brush and pan, by myself. And after a 12-13 hour shift I just want to go home and eat my dinner.
Though I'd also like to add a couple more rules that people should follow in a movie theatre:
9: At least try to clean up any rubbish you leave behind. Seriously. I know Popcorn has a tendency to go everywhere (which is why Cinemas store it in a special heated cage to placate it), but coffee cups, Popcorn cups, drinks bottles, and apple cores should go in the bin. It's basic etiquette, and it means the theatre is cleaner for everyone. This goes double if you brought your own food in.
10: If there is a problem, tell a member of staff. If someone's using a phone, or making noise, or something's up with the film, and it is bothering you go find a staff member, and they'll sort it out. the cinema I work at has, at most, 3 members of staff on at one time (usually 2), and this includes the projectionist. We have other things to do besides sit in on every showing of every film, and so we can't tell if someone's being unruly. We endeavour to check in when we can, and shows that are likely to be trouble will likely have someone sitting in (I have seen the last three Twilight movies MULTIPLE times in the same day; I don't get paid enough for that). If you come out at the end and complain then we can't do anything about it.
EDIT: Currently the "Turn off your Phone" message in our theatre is done by The Muppets. If you ignore Kermit the Frog telling you not to use your phone then we are well within our rights to slap it out of your hand and crush it under our boot.
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