Ghost,
I hope my response didn't sound too judgmental. I certainly didn't intend it that way. It sounds like the two of you have a system that works well for you. If both of us made similar money (perhaps at some point in the future...) we'd have a good reason to revisit our arrangement.
Both of my kids enjoy movies -- especially animated ones. My son, who is older, will leave the room the second he thinks something scary is going to happen. It's pretty cute.
My younger daughter will stay even if it is a bit scary.