It would be interesting if elections were more like shareholder votes in a corporation: you get one vote for every dollar in taxes you pay. Even if that were strictly for advisory measures, at least everyone would know how the people actually footing the bill felt about it.

Typical.

Isn't the U.S. a representative democracy, not a corporation democracy? Why should people who can afford to, run the system? Oh wait, that's how it works anyway. Nevermind.

"A democracy cannot exist as a permanent form of government. It can only exist until the voters discover that they can vote themselves largesse from the public treasury. From that moment on, the majority always votes for the candidates promising the most benefits from the public treasury, with the result that a democracy always collapses over loose fiscal policy, always followed by a dictatorship."
-- Professor Alexander Tytler over 200 years ago

The reason the top 50% of earners pay 96% of taxes is because they make substantially more than 50% of the income. Think about it this way: list the numbers one to one hundred, then add the top 50 numbers, and the bottom fifty numbers. Not exactly even, are they? Now compound that by considering that the top fifty percent of earners can (and in the US do) make an unlimited amount of money, while the lowest few percent make a tiny amount of money. Is it inequitable to expect that those who benefit most from civil society pay for it? Is it unfair to expect that those who make the least don't give their last dollar to taxes? It also depends on how you define taxes and how you account for taxes that are deductible from income for other tax purposes... All of these arguments are more complicated than a one-line statement or a facile pie-chart.