Except then it affects poor people more as consumption of things that people need makes up more of their income than the rich who have more disposable income, savings, capital and investments. Thus driving even more wealth inequality. But HN readers are more of the "Temporarily Embarrassed Millionaire" types...
So you don't apply VAT to inelastic commodities. We have in fact figured this shit out. Austrian or Keynesian are not the only two choices available to us, despite what some would try to lead you to believe.