I must say that it was a fan favorite for 2 weeks with my young ones!
They showed it to everyone, the story really isn't meant for adults indeed but if it makes my kids that happy it's a good movie in my book :-)
(Same with the new castle, they really enjoy the big one with all the moveable parts and the new "6 shooter" My son was shooting at my formations for over 30 minutes without getting bored :-)