Well Gill, in the fairytale, the well born princess was able to prove she was a well born princess (not that she was trying to you understand) cos they slipped a pea under - oh I dunno - about a hundred mattresses, and she was still able to feel it, so they knew she came of good stock and was worthy of marrying the nerdy Prince who set the whole thing up in the first place.
That's how it goes in fairy stories. or it was back then. Not that I was there.....
Whereas - well, thi Prince is just very handsome and charming and glorious!