For me, movie theaters are the definitive way of seeing a film. I am lucky because my hometown of Toronto has a true love of film - obviously, since we're home to one of the world's largest public film festivals! If a film is made sooner or later, no matter how big or small it is, it will get a release in Toronto (99.9% of the time anyway...) and the crowds here often add to the experience, they cheer, applaud, ooh and aah at all the right moments, very rarely do I have any experiences with other people that ruin the movie for me and I see a movie in a theater on a weekly basis.
As far as concessions go, I'll pay a lot for the occasional tray of nachos but normally I just bring in my own water bottle and some candy I grab at a nearby drugstore. Big deal, you don't want to over pay for popcorn? Then live without friggin' popcorn.
At this point I rarely ever watch a film initially on DVD, partially because I will pause it, I'll get distracted, etc...And that's just not the way to experience a film, I want to watch it in one straight shot with no interruptions but I'm just too fidgety to do that at home. But in a movie theater that's it, I'm in for the 2 hour ride, no ifs, ands or buts. I love goin' to the movies and hope the day where my only option is to watch it on a TV never comes.
One of my fondest memories of 2009 was seeing the new Star Trek film opening night and the cheers, the gasps and applause at every little twist and turn that this crowd of 400 people gave the film...I wouldn't trade that experience of that, of feeding off the energy of hundreds of people loving a movie, for seeing it on a couch in my basement in a million years.