The reason flat and sales taxes are opposed is because they are deliberately designed to favor the wealthy.

The poor pay a major proportion of their salaries for necessities. The rich can divert a larger portion to investments or savings and have much more choice in what they buy. A sales tax savages the poor. For the same reason, a flat income tax (or one without a low-income exemption) hits the poor proportionately much harder than the rich.

When you add the accounting tricks the rich can afford to deal with the deliberately baroque complexity of the tax code, and the ability to write off losses on investments, the only real disadvantage they have is capital gains, and they are constantly working on reducing or eliminating that. If they had their way, they would pay no taxes at all, presumably because they are using every spare penny they have creating jobs for the ungrateful wretches that work for them.

As for your comments on power, they all apply equally to the private sector, where they are exercised by those with no mandate or supervision by the voter or the constitution; men who have no loyalty except to themselves, or the narrow interests of the soulless and single-minded organizations they work for.

I'm not disputing what you say in its entirety, but you must realize that the opposition to your policies does not arise solely from the misguided pig-headed obstinacy of your opponents. Power will always fill a vacuum, and commerce has never shown a reluctance to extend and consolidate its own. It matters little to its victims whether it is yielded by a government or a corporation.