"Monarchy is indeed a government which requires a high degree of civilization for its full development ... An educated nation recoils from the imperfect vicariate of what is called a representative government." -- Benjamin Disraeli
The British system of government is far less costly than that of the US.
You pick how you are goverened according to your ethics, not according to how much it costs. I am pro-democracy and I am not a hypocrit. This fact prevents me from supporting a political system based on inherited political privilege, like Monarchy. I am English. I think most British who support the Monarchy do so because they don't want to admit to themselves that there is something wrong at the core about the way their country is governed. If we'd gotten rid of the Monarchy in the past, we'd probably have yearly celebrations about it. But no, we still have them, so we celebrate the opposite instead.
I think you missed the point of my reply - I did not raise the matter of costs, and I agree that they are not the overriding factor.
The Disraeli quote is to the point: the "representational" part of representational government is thorny, and pretty much ensures that a ruling clique is put in place whose interests do not mirror that of the electorate very well.
The constitution of representational democracies always put in place a watchdog over the powers of parliament: in the US, it is the legal system. In Turkey, it is the army. In the UK, it is the monarchy. Many people seem to think that law courts are an obviously superior guarantor of democracy than monarchies, few are able to argue the point well.
The British system of government is far less costly than that of the US.