It's just common sense that common theaters are not setup to be a church like experience. Going to the movies is a social experience that involves going out in public and experiences all of the things that come with being out in public.
To be sure, people who attend movies should try their best to be courteous to their fellow moviegoers, but a theater patron just has to realize that it's not always going to be a pristine experience.
For a person to expect a totally sterile experience is just not realistic - at least not with mainstream, modern theaters.
"It's just common sense...."
Bingo! And that's the solution to this issue. That some people must endure others who do not have common sense is just one of those things that goes with going out in public. The same goes with inappropriate cellphone use, farting, too much garlic in foods in combination with the general public.
The folks who complain about cellphones on this thread would be much better off if they focused their energy on, say, coming up with new and creative Homeowners Association Rules dealing with paint color, shrubbery, and lawn maintenance.