Rob brings up a couple of interesting questions, but he also has a misapprehension. We do, of course, have a continuing equivalent to the royals: money. Everything you can say about the royals, money does in the US. By money, I don't mean the *monied* -- I mean the actual thing: the filthy lucre, the gelt, the moolah. Greenbacks. But going the other way, with the personification of money, we also have some quite long bloodlines -- a century and a half after John D. started making the big bucks, many of his descendants are still filthy rich and effective political manipulators as well. Nelson Rockefeller was governor of New York for 14 years and later a US vice-president. Jay Rockefeller was governor of West Virginia and then a US Senator until five years ago, a hundred and seventy five years after the birth of John D (which came a year *before* the royal marriage that led to the House of Windsor.) The House of Rockefeller has a worth estimated currently at $11 billion.
As for the Royals who have now departed for Canadia, I don't think they'll be eating cat food any time soon. They had an extremely powerful weapon in their negotiations with Crown: what if Harry *did* endorse, say, a brand of cat food, or, god help us, a brand of condoms. That would certainly be unthinkable to the holders of the Royal Purse, and I'm sure they made a nice financial arrangement for the ex-royal highnesses, to prevent any such calamity.