Well, I can certainly understand each criticism except the ones about the tights and her hair. I am in a public profession and sometimes have to endure criticisms from people who see me. I really do not dress to please them any more (and I avoid reading or hearing criticisms if I can although I suppose I should pay some attention, as I used to, as accepting criticism improved my style and appearance, if I am honest).
As to my own criticism of her (and I criticized her food and makeup), I am shocked that she would go up against one of the biggest causes espoused by her future father-in-law: the rightful and kind treatment of animals. What an odd thing for someone about to marry to do; what's the point in antagonizing the in-laws?
The make-up is just a personal opinion, I certainly did change my own make-up after hearing critiques of it, and I listen carefully to the views of certain people who I believe are up to date on how people should wear make-up (it does change over time, as we all know).
And if no one has told her about the royal injunction against foie gras, that speaks volumes as to their various degrees of communication. Camilla obviously didn't want to tell Catherine what to do, but in many (successful) relationships, a future husband takes the time to inform his bride-to-be about familial quirks, and the bride-to-be (at least in public) respects those quirks (especially right before the wedding, when everyone is trying to get to know each other and true bonding hasn't occurred).
I agree that I'd never go back to that restaurant again (and it's off my own personal list as well, so someone needs to be fired or severely disciplined). One paper has a highly professional picture of the foie gras in question, possibly from the restaurant's website, and it seems to give the restaurant a type of free advertising.
Kate's going to have to realize that's the consequence of every public action: many things beyond her control (including the free speech of the entire world, now memorialized on the internet) are going to occur. Some positions have this downside, and if she wished to be completely private, she'd need to dine inside one of the family's own places or at the houses of friends.