My family and I love all things Disney! We have annual passes because we live only about 45 minutes away from the Magic in Florida. We go at least twice a month and enjoy many a "staycation" at the House of Mouse.
(If you read my blog with any frequency, you'll notice most of my pics are from Disney too! )
Disney also provides lots of "springboards" for writing. Lewis has recently shown a huge interest in writing his own book. This is probably because I recently finished my own book on "How to Write an Expository Essay".
In any case, he is writing because HE wants to and is excited about the process. This is great! He is expressing his own ideas with his own voice which sets him up quite well for the future. To me, writing is more than copying/emulating great authors or the ability to write about a historical time period or even being creative. It's about having a bank of specific, structured patterns and resources to pull from in order to produce work (i.e. papers & essays) that can express AND communicate in a variety of situations and careers.
So yes, writing for fun is important, but remember to take advantage of the opportunity to develop the skills that your child can call their own.