Watching a movie at home is cheaper (7 $ HD for the whole family), a better experience (no smell of whatever food they sell in cinemas), not having to deal with people who talk during the movies, etc...), less effort (I'm home already), you could even argue better for the environment since we don't need to use any mean of transport.
I really do not understand your analogies, they don't make sense to me.
Do you only discuss books you have read with and at the same time as your friends?
If I wanted to go to dinner and talk, I'd hang out at roadkill point with the crows, and make fun of the redtailed hawk behind her back.~
I remember back when going to the movies at a cinema was a great way to date someone without letting them know exactly where you lived--in case they turned out to be both wrong for you and obsessive--and without revealing immediately that you can't hold up your end of an unprompted, free-form conversation for four whole hours. It's a lot better value when you don't have to pay for your kids' tickets and meals, too.