And from the perspective of someone who actually works in tax: the "FairTax" simply pushes all the complexity to everyday transactions, instead of minimizing it to periodic transactions occurring 1-2 times a month (with reporting once a year). It would hugely disincentive paying for actual things, and artificially incentivize (untaxed) services over (heavily taxed) goods.
Moreover, the "FairTax" rate would be 30% or more on all purchases. Not only would the FairTax would obscenely regressive in effect, but a tax rate that large would push a substantial portion of the economy underground!
There's so much wrong with "FairTax" that it should be called "Ridiculous Tax."