Excellent point- the FairTax is a wonderful plan for those Americans who don't "need to buy things". I've even heard it called a "voluntary tax" because buying things is not a mandatory behavior. (Of course under this definition, the income tax is also voluntary)
There is no way to analyze how the FairTax would impact anyone's financial situation, because it is all pie-in-the-sky guesstimates based on faulty assumptions to begin with.
And the transitional effects on the value of all capital, and the suppression of consumption in this country would wreck our economy.