I think it's a great convention for Haskell to use. Learn You a Haskell uses it to wonderful effect. Haskell is hard to learn (at least at first). Even for people with a functional programming background. The cartoons makes it look like a children's book, which has a psychology effect of making the material seem easier.
learnyouahaskell.com
at first.
when/where did adding frames from movies get popular?