Theater etiquette

I've been going to the AFI Silver theater for the past 3 weeks and so far everyone I've shared the movie-going experience knows to be quite in the theater and not use their phones. Apparently this is not the case at the Alamo Drafthouse which is a theater is Austin with a strict no texting/cellphone use policy. A women used her phone to text and was asked to leave the theater. She followed this up by leaving a nasty voicemail with the theater complaining about being removed from the theater. Then the Alamo Drafthouse used the voicemail as a PSA about theater etiquette. And it is awesome (though there are swearwords).