Seconding this. The idea that rich people have a target (after-tax) income and will charge whatever it takes to hit that income is absurd. The target is infinite, and they are already doing everything in their power to make their income as large as possible under current conditions. The fact that their income ever got so large is an indication that they already have too much power to increase their income at the expense of others (not least by convincing a share of the population that their wealth/income is inevitable and/or a necessary condition for the prosperity of others).
