I think she is probably completely different at home. Having a boring public persona is probably a way of distancing the press and all us other nosy people from her real life, which I suspect is rather lovely.
When you think about it, her public appearances are not all that frequent, which leaves a lot of time to do exactly as she pleases. Most people have jobs where they are scrutinised, albeit not quite so publically, and have to put on a persona to deal with customers/pita colleagues etc. Probably the same for her.
I like a pair of nude courts and if I had her legs I'd wear them to death too. As it is, I own numerous pairs of pretty painful shoes but live in my ankle boots.