There is a very big difference between a private visit and a "private visit". When Harry went and surprised those kids at the studio; all the pictures we got were from cellphones of people who happen to snap a pic (very low quality). With Kate we get prefect HD pictures taken by a photographer.
"do you think kate's extreme weight loss is because she now has to wear designer clothes and they mostly make them in a size 0?" She is not reQ to wear designer. If u spend $150,000 in taxpayer money/year on clothes they make what you want in what size you want. KM isn't borrowing runway samples, designers are making custom/bespoke (often unflattering & ugly) outfits for her. Kate Middleton is the size she is because SHE chooses to be that thin, "all part of the plan" in her own words.