Every redistribution of the tax burden has winners and losers. With the FairTax, it's not poor people who consume very little because they get a bigger subsidy than before. It's not those people who make far more money in a year than they can possibly spend (especially once you cut the now tax-free real estate[1] and lavish consumption on foreign holidays out of the picture). It's the average working person.

[1]I've yet to see a sane argument for why you'd want to give property speculation a massive tax advantage over buying and selling consumer goods