I'm going to talk about electrons for a moment.
Electrons are extremely important. They transmit much of the energy we use to power our society, including the computer screen you're reading this on right now. Everyone uses electricity, everyone understands how important and valuable it is, and everyone expects to pay a price for using it.
But electrons by themselves are worthless. You can have as many electrons as you want, but they don't do you any good in your appliances if they're not connected to a voltage to make them flow and do work. So you can keep your electrons if you want to be possessive about it. They just won't be any good to you.
Dollars (pounds, euros, yen, rubles, shekels...) work the same way. They have no value by themselves; the only thing that makes a dollar valuable is the fact that someone somewhere will accept it in trade for goods or services of real value. So, you can whine and complain about the government taking away YOUR dollars as taxes, and how they're punishing you by confiscating wealth, but guess what? If everyone were to decide tomorrow that we're abandoning dollars for barter, you'd get to keep all your precious dollars, and you'd be kinda screwed, and the thing is, if you're not obliged to spend your money in ways you don't want to, no one else is obliged to ACCEPT your money if they don't want to. So bitching and complaining about being taxed when you're rich is kinda like bitching and complaining about not getting to keep all of your electrons.
But there's more. Much more. The economics of electricity favor economies of scale; it's easier to transmit a whole lot of electrical power to one user than it is to distribute it through a vast grid of many small users. With the money system, it's kind of the opposite. Money is really, really useful for making economies flow well, but it works best when everyone uses it. You're better off being able to pay your workers a salary instead of having to supply them with clothing, groceries and housing. Yet the VALUE of money as a system increases greatly for those who use more of it. At the subsistence level, I don't care much if I'm paid in money or food; I'll just spend the money on food anyway. At the middle-class level, hey, I'll prefer the money because that lets me get a mortgage and life insurance and maybe a pension plan. At the highest income levels, well, money is absolutely indispensable; enormous wealth today depends on being able to conduct transactions using money, speculating on share prices, etc.
Money (not wealth, but money) is a system, a service provided by the state and the people as a whole (because all of as are prepared to accept it in trade), but the high end users gain far more benefit from it than the low end users. It therefore makes sense, solid laissez-faire capitalist free market sense, to charge a higher premium for the use of money at high income levels than for lower income levels. In fact, it's very much in the interests of rich people to subsidize the use of money by poor people.
Another way to think about the relative power of money: Who can do more with a million dollars? One millionaire, or a thousand people with a thousand dollars each? Assume living expenses are $500 per person. The millionaire has FAR more economic power with his money than those thousand people combined. Or think of mortgages: If $200,000 all at once so you could buy a house wasn't worth more than $200,000 spread out over time, nobody would be willing to pay interest on a loan. And yet we do; we're willing to pay the bank $300,000 over time in exchange for the use of $200,000 right now.
So, my point here is that progressive taxes are not in the LEAST bit unfair, and it's absolutely appropriate that people with a low income should pay little or nothing in income tax, while the very rich should pay a high marginal rate. It's not punishment. It's a sound economic choice.
Final point: If you think the user fee for money is too high, don't use so much. Try barter instead. Oh, that makes it impossible to cash in those stock options? Gee. What a shame.
