I can watch movies over and over at home but for some reason, I cannot always absorb the entire plots, dialogue, ect. At the theater, sitting in that one spot helps me concentrate on the film better.
When I saw DEEP RED (the R rated USA cut) at the movie theater a few years ago, it was so much more enjoyable than my DVD viewings. Same for RE-ANIMATOR and DEAD ALIVE which lent themselves to the theatrical experience better than my previous home viewings.
However, the first run theaters here in San Fran have waaaaay too many distractions to even bother wasting money going. You are guaranteed some irritating moment even if you pay a premium