I don't think any of us would consider pictures of us or a family member shot from this location to be fair game. We don't consider using telescopes to see us in places where the naked eye can't see to be appropriate. If it's nasty to point out that the same courtesy should apply to Kate Middleton, then I guess you and I disagree about that. I think you may have been under the misunderstanding that the photographer snuck onto the grounds. That is not the case.