The Biggest Problem is Ignorance

I recently went to see the final chapter of the Harry Potter series, "Harry Potter and the Deathly Hallows Part II".  I was especially excited, because it was at an IMAX in 3-D with digital surround sound that blew me out of my seat so this was the complete experience.  Minutes into the film however I became aware because of a loud crying, that the lady two rows behind me had for whatever reason decided to bring in what looked to me like her newborn baby.  Seriously?  Maybe you couldn't find a babysitter but really, you thought that a baby could sit through the intensity that was Harry Potter IMAX?  I would understand Winnie the Pooh or something similar but thats just inexcusable.

http://sunnyskeptic.files.wordpress.com/2009/08/crying-baby-party-56800676.jpg

This hit it on the head for me, on what may be the biggest problem the theaters are facing.  Its not the expensive tickets, or the way overpriced concessions, but the other people in the movie that for whatever reason decide its ok to ruin the experience for everyone else.  In the last three movies alone I can specifically remember moments that took me away from the film and ruined it for me.  Along with the lady with her newborn (and unfortunately this happened again during Captain America), unattended kids that run around and talk the whole time, or the person that decides to text or look on their bright phone through the whole movie need to show respect for the rest of us who pay to see the film.
There should be some restrictions on who can be let in to see non kid films like there is with a rated R movie.  Other than common sense, which should be understood before bringing a little kid into an intense movie, then at least if your courteous (thats a big IF) you take them out when crying.  If you do that then you will miss most of the movie anyways because your kid is crying the whole time.  What is the reasoning here?
As long as you are seeing a movie with hundreds of others, you will never get past this problem that is harder and harder to put up with when we spend so much to see a movie.  I was so excited the other day to see Harry Potter in IMAX, and after the $40 dollars or so I spent on tickets and concessions one lady with her crying newborn ruined it.  I for one will definitely think hard before I want to go risk spending that kind of money for a 2 hour movie next time.