Xmas show mistakes, anyone ever notice this?

Ok so today Yahoo had this little story about mistakes made in Xmas shows, http://primetime.tv.yahoo.com/

Now I had another one... When I was a kid I remember watching "Frosty the Snowman". He came to life when he wore the hat. In one scene he is going down a hill with a bunch of kids, or maybe it was one I forget, but his hat comes off while he is going down and nothing happens. I remember asking my sister about it, and she said "maybe it fell off by accident". Well its a cartoon, that means someone had to draw it coming off.

Just seemed strange that the artist had no idea about the story he was writing, and this made it to the show.