Every has their horror story of going to the movie theater with rude people all around. I have had the occasional talking person behind me, and even some seat kickers. The stories I have heard from others are horrible, ranging from talking on cell phones to taking pictures of themselves with their cell phones while the movie is playing, to fights breaking out.
I have always been the one to not talk during a film, unless I had to ask a question of someone I was with concerning the movie's plot. One of the first films I remember seeing in a theater is Jurassic Park. By then I was around the age of ten. Today, there is a huge market for very young kids to go see movies, and by very young, I mean in the 3-4 range. There is plenty of blame to go around from the culture, to bad parenting, and to the movie industry itself who markets to these young children.