Sorry for making the mistake, I would edit if I could.
You can metric the system however you want. It is just out of context under the FairTax to focus on labor wages. Warren Buffet only makes like 600k in "wages" and just pays the capital gains taxes on everything else he cashes out (or consumes). That's why is tax/earnings is so low. But calling the FairTax progressive by saying the rich who save/invest will be paying less is short-sighted. One can just as easily do this exact same thing with tax-deferred accounts or other complicated financial engineering today.
Yes, even if you make $10MM labor wages in a year, you will still get the prebate. Adding X,000 to your $10MM income will barely make a dent, but all citizens over 18? (I believe) will receive the prebate, similar to a social security check, and this can have significantly positive effect on the lower income bracket--especially coupled with the lack of withholding.
By the way, to say one can only spend 2,000 on taxable items is impossible. Even if you simply look at the "essentials"... food, clothes, utilities, insurance, & transportation, you will easily top $2k in taxable spending but that isn't the point.
If you spend all your discretionary income buying used homes, that is certainly your prerogative and would owe zero upfront tax on that purchase. You could just as easily put the money in a 401k type investment or any other tax-deferred account today and get the same effect. The current system uses a tax deduction and then the net income is what is used to calculate your tax. The difference though, is when you cash out that investment, you will pay the standard rate on the principle, but only 15% on the capital gains. Does that make sense? In the FairTax you will pay the standard rate on both the principle and the capital gains. The complexities would be gone. I think the bill itself is only around 100 pages. The high-priced tax accountants and lawyers won't be able to finagle P&L statements, establish irrelevant corporations to funnel money through, and lobby for special deductions.