But how do they pretend? It's not them who judge but the people meeting them or reading about them. Here in Germany a SAR-pilot, of the military or privately employed, is a top employee/member of military staff and surely can afford a honeymoon at the Seychelles. Alas, as they don't need the extra privacy, they can go on a much cheaper, but still luxurious holiday.
As for Catherine not working: sure, as a millionaires daughter she didn't need to work. But as granddaughter of "Lady" Dorothy Goldsmith, whose two children both rose from humble beginnings to self-made millionaires, she surely inherited and was taught some sort of workethic. But as she as a lot of normal people are used to, worked from a homeoffice, she was not seen working. Instead of playing for the ranks of the media, she kept a low profile and accepted her monikers - but that doesn't mean she didn't do anything for others.
I believe Catherine and William are just that: Catherine and William. Nothing more, nothing less. One day they are TRH The Duke and Duchess of Cambridge, representatives of the Uk, the next day they are Fgt. Lt. and Mrs. William Wales, pilot and his housewife spouse. On their honeymoon they are fairytale Prince and his new princess. On other holidays they'll cycle round Britain and sleep in a tent on the ground (Thats what Boris Johnson told when he explained that he had given them a tent and bikes for their wedding: that they plan to use it!) But in both Royal and "ordinary" roles (which have a lot of variations to it) they seem to be authentic people. And that's what others feel on meeting them and that's what comes across as positive.