I've heard that a lot of children's media often looks to help encourage pattern recognition (eg: counting the Very Hungry Caterpillar's foods or the structure of a Blue's Clues episode), but I don't know how true that is.
I've heard a corollary to this. Kids often love to watch/read the same thing because they recognize the pattern and know what is coming up next. This gives them comfort and a routine.
As an adult I love recognizing the patterns and anticipating what's coming next! The only difference is the patterns get more complex :)