Let's rebrand the flat tax to the “Drug Dealer Relief Act” since criminals will never pay income taxes, flat or not. Then refer to it that way every time. When anyone says flat tax, you say "You men the drug dealer relief act". Feel free to disseminate this re-branding far and wide.
Even Plato knew this 2400 years ago.
"Where there is an income tax, the just man will pay more and the unjust less on the same amount of income." – Plato in 400BC