But she's Californian, and living in California! The whole thing has a very SoCal vibe, so as always, the imagine is confused.
If she'd been shrewd enough to remain on good terms with the royals, she could have still done the occasional appearance at Trooping or Sandringham without compromising her 'freedom', yet maintaining some sort of royal mystique which she could have marketed. As things stand, however, she was only royal for about 5 minutes, and that was years ago. She's royally messed up her lucrative USP.