I've posted my feelings about this before, but after reading/seeing story after story that talks about the current box office "slump," I feel I should chime in again.
Here are my reasons as to why I rent DVDs from Netflix/buy DVDs of movies I love more than I go out to a movie theater.
1. The price of admission
$8.25 to see one movie? The average price of a DVD is between $14-$25. Seeing a movie twice in a theater covers the price of owning it once on DVD.
2. DVDs have extra things that you want
While the extras listed may be a fraud from time to time (fluffy director talk, EPK puff-pieces, deleted scenes that add nothing interesting), a lot of commentary tracks, deleted scenes and behind-the-scenes documentaries add more to the experience of the movie itself. Seeing 25 minutes of commercials and movie trailers for things you don't care about aren't worth your time.
3. You aren't distracted by annoying audience members
I'd rather deal with my dog occasionally barking at random noises than deal with babies crying, cell phones ringing (and the people that answer them) and people that won't shut during the movie.
4. If you have to go to the bathroom, you don't have to miss anything
Just press 'pause' and go. In a theater, you can't do that. Good luck with trying to find your seat when you get back.
The reasons why I still see certain movies in a theater:
1. Seeing things on a big screen is cool
You see a lot of things in a larger-than-life kind of way. Things are still smaller in home entertainment, even with a big screen TV.
2. Immediacy of seeing a brand new film
When you see it in the theater, the movie is brand-spanking new. When you see a movie on its opening weekend, not everybody you know has seen it and has an opinion on it.
3. Sound quality is top-notch
You feel those spaceships fly past you, those bullets fly, the music, etc. At home, it's not as intense.
So there you go. There are plenty of good reasons for and against, but with all the paranoia I have with being in the company of strangers, I stay close to home.