Earlier quoted context omitted.
That's still a disincentive: my effectively hourly rate decreases the more hours I work. Not sure how that's fair. A flat tax is the only fair tax. You make more, you pay more, but you aren't taking an effective pay cut per hour based on simply working more.
Most flat taxes do not land in the "you make more, you pay more" scheme. Instead, they are in the "you spend more, you pay more." Which, doesn't sound bad, necessarily. However, there are two problems that I see. I suspect there are more. First is that what you spend is only related to what you make. Specifically, it is relatively easy to find ways to not spend money if you have extra. What this means is that, at an…
I think you are missing the point. If it is truly a flat tax, the number of dollars you are taxed goes up (in a directly proportional way to the number of dollars you make). So you DO pay more the more you make. It isn't even a logically arguable point.
"a flat tax actually gives a very easy way for high income people to have a lower tax rate.":
-- again that's a completely illogical statement. If it is truly a flat tax *EVERYONE* has the same rate -- that's the very definition of a flat tax.