I agree that 10% of someone making 10k/year is a lot harder to stomach than 10% of someone making 1mil/year. But I don't see how you can say it's "unfair". A flat tax is the epitome of fair. it's _the same_ across the board.
The only unfair thing is taxing wealthy people way more just because they *happen* to be more successful (whatever the reason).
And no, i'm not one of them. I'm pulling in 40k currently.
If you went a flat tax, then yeah, low income people would suffer at first, but I'll tell you what, there would be no greater motivation for them to get off their ass and improve their life/situation/job/whatever.
not to mention, they'd actually vote on stuff to help everyone, (since everyone is taxed the same) instead of voting on freebies because they don't pay tax anyway.