In defense of us non-normal people, not everyone sits and watches the whole movie. Sometimes it's the comfort of listening to the movie while you are doing something else. You can always watch when the great scenes come up! Why do people listen to the same song more than once? What's up with that? You've already heard it. It's not going to change. Hmmm...
When my brother was a little kid, my parents got him a toy that came in a box with a cellophane window in front. Apparently he got a big kick out of putting his other toys in the box and looking at them through the window. Not sure what the original gift was.