As I have often mentioned on threads dealing with the American War of Independence, taxation even during the period of Royal "absolutism" NEVER even approached the extortionate levels forced on us by our "freely elected" representatives.
One columnist (I think it was Joe Sobran) pointed out that medieval serfs paid less in feudal fees and taxes, as a proportion of his gross income, than does a modern citizen.
The Royal family may be exempt from the bulk of taxes. I do not regard this as the family shirking its "fair share" so much as the population at large being the victims of wholesale daylight robbery. This is not the fault of any living English monarch; HM does not impose taxes of her own will, but functions as a highly paid rubber stamp for Mr. Blair's party or whatever other scoundrels can obtain a Parliamentary majority. Consider this: assume that the English monarch became an activist Libertarian, revived the Royal prerogative, dismissed Parliament, and abolished Inland Revenue. How many minutes do you think would pass before the monarchy was officially dissolved by the Lower House?