Plato had it right on MPs' expenses. This from The Republic:

"We also have to make sure the guardians do not become like sheep dogs that turn into wolves and abuse their power to harm their fellow citizens. Therefore the guardians will have no private property, they will live transparently, they will be provided for out of taxes, and they will live together communally. First, none of them should possess any private property beyond what is wholly necessary. Second, none of them should have a house or storeroom that isn’t open for all to enter at will. Third, whatever sustenance moderate and courageous warrior-athletes require in order to have neither shortfall nor surplus in a given year they’ll receive by taxation on the other citizens as a salary for their guardianship. Fourth, they’ll have common messes and live together like soldiers in a camp. We’ll tell them that they always have gold and silver of a divine sort in their souls as a gift from the gods and so have no further need of human gold. Indeed, we’ll tell them it’s impious for them to defile this divine possession by any admixture of such gold… Hence, for them alone … it is unlawful for them to touch or handle gold or silver… In this way they’d save both themselves and the city. But if they acquire private land, houses, and currency themselves, they’ll be household managers and farmers instead of guardians – hostile masters of the other citizens instead of their allies. They’ll spend their whole lives hating and being hated, plotting and being plotted against, more afraid of internal than external enemies, and they’ll hasten both themselves and the whole city to almost immediate ruin."

H/T: Fraser Nelson - The Coffee House