Anyone earning over one million dollars per year has all their family's basic needs covered PLUS all the luxuries anyone would ever need. The rest should go into paying back society as they are the consumers, the purchasers who made these people such vast fortunes. This is called 'Giving Back', but with the help of the government to ensure that the fat cats do give back..
When someone earns more than 10 Million dollars per year, an even higher rate should go into effect of 75% as this still leaves the earner with many millions in the bank. These fortunate high-earners should be happy to put their vast sums to work for the benefit of those who allowed them to earn such exorbitant sums, the general public. It's their patriotic duty to do so.