I'm all for the Royals. To say that the only income the Royals bring into the country is a few quid for tourism is a dim view. The Royals tour the world hawking British industry and goods. After nearly all Commonwealth summits there is normally an announcement that we're going to supply such & such a 3rd world country with tractors/agriculutral equipment/ missile/bombs/warships or planes. That doesn't happen by itself. People say the Royal Wedding cost £20M to police but how much money was made in selling crappy plates & mugs, TV rights abroad, advertising during ad breaks on commercial stations, all this stuff stimulates a currently dead economy. ****, we (as country) made money out of Diana's funeral.
Also under our constitution say a Prime Minister was to lose the plot and suffer a breakdown and decide to nuke Russia, allow interbreeding & join the Euro, who is the only person who can legally step in and have the Prime Minister committed? The Queen. Handy little backstop in my opinion.