To each his own. If you own a home theater you like, you have little reason to go to movies.
I have an HT system I love, but I still go to movies. I live in the city though and have two decent multiplex cinemas to choose from. But going out to a movie by myself (leaving wife and kids at home) is an occaisonal solo night out for me. No kids, no distractions at home, no falling asleep.
Last movie I went out to was Munich, it was good. But the presentation would have been just as good at home, if I could get three straight hours of silence there.