Just because they are not seen to be working confuses people. They work from home offices dealing with correspondence future events. Necessary administration
Remembering the extensive staff employed by the RF, it would be fascinating to know how much of this involved actual work and how much is simply telling some secretary what to do. Admittedly I'd rather they weren't there at all, but as long as they're publicly funded for their "work" the rate of it isn't just low - it's a disgrace
The excuse is usually that it's important for them to spend time with their young families while they have the chance, but funnily enough there are millions of working families who feel the same - except they don't have somebody else to pick the bills up for them
And speaking of bills, why do folk so often insist that William and Harry pay for the private stuff in their homes themselves - do they have access to the accounts which the rest of us don't? Bearing in mind the example of the Queen's household, who applied to a poverty fund for money to heat the palaces, is it really likely they'll think "Oooo no, it's only right that we pay for such-and-such ourselves"?