Withnobsonit - I think that really is a problem - the "Disney Tat."
Our family had a lot of dressing up things - and made masks and outfits regularly. We had rabbits and Alice, caterpillars and bats, princesses and jungle explorers, tin men, pirates (one with his own song), magicians and witches and cats... and Tom (who always won games with captain Najork)
Alongside this we had "ordinary" people who had amazing adventures
Princesses aren't the only imaginative play you know - though I accept you can be a pirate princess up the tree/climbing frame if you take the frilly skirt off!