Why not asking them to sacrifice something in turn. Say manhood and permanent disfigurement. Or a few limbs each? Nothing big. They can still live lavishly, but it would be absolutely fair trade wouldn't it?
Well kings used to leave capital quite often... Why pay your own upkeep when you can get others to pay for it. By visiting them. It is not like they can stop the king...
Actually most western swords weigh pretty much the same or even less than Japanese ones. At least ones actually used for anything other than ceremonies. Probably in sub 1kg to 2kg max range. With more of them being between 1 and 1.5kg...