Why do none of the states tweak their sales tax numbers like that?
State sales taxes are calculated using the NET price as a base. Income taxes are calculated using the GROSS income as the base. To compare the two, you need to use the same base. Thats all the Fair Tax people are trying to do. They are trying to be technically accurate.
Here is a question for you: If you spend all of your income on taxable items and there is a 23%(30% by your standards) federal sales tax, what percentage of your income did you spend on the federal sales tax? A) 23% B) 30% C) 18% D) 124%