Half of the citizens pay income tax - over 100% would pay a consumer tax.
Income tax was proposed by Karl Mark - a consumer tax was advocated by Alexander Hamilton.
Income tax began at a very low rate and only on high earners. - a sales tax rate on new goods and services would be self leveling. If the rate is raised and people buy less revenue would decrease and the rate would have to be decreased to get back the revenue.
Income tax can not be avoided if one works - sales tax can be avoided by not buying new goods.
The flat income tax has been studied and failed. The Fair Tax has had over $30 million spent on studies and is backed by hundreds of economists.
Learn all that you can about the Fair Tax at www.fairtax.org