Folk tales were initially not aimed at young kids at all but for the entertainment (and maybe also illustrating morals) of adults. When the tales are adapted f

Folk tales were initially not aimed at young kids at all but for the entertainment (and maybe also illustrating morals) of adults. When the tales are adapted for the kids, the violent themes are often tempered down. The story themselves are often changed. Just visit a book store to see the numerous adaptations are 'Little Red Riding Hood'. Also, for young kids, the book is filtered through the interpretation of parents. So they can mellow down certain parts based on their kid's sensitivities. Also, in books, the really gory parts are often left to the imagination and not every scene is pictorially represented. Fortunately or unfortunately, each and every fact has to be shown in some form in the movie. Movies tend to be more visually stimulating than books and tend to pull in the kids more. On the other hand, books have the luxury of being able to provide stories tailored to each age group. Movies have no such luxury if they are to be financially viable. Also each movie wants to have a villain more scarier than all the ones before and visuals (earthquakes, huge torrents of water anyone) much grander. You invariably endup with something frightening for kids. But above all, kids' imagination are more volatile and fertile than ours. Their view of the world is incomplete and hence their interpretations of the same scenes could be radically different and unpredictable. Case in point, My four-year-old was frightened of 'My Neighbour Totoro', especially, the scene of Totoro on the tree at night and the catbus :) .