Why is a national sales tax unfair? Ok here's why. Say a doctor makes 200 grand a year. Right now his income tax would be 35% of that or about $70,000. Say he typically spends around $100,000 a year on his purchases and bills. Under the national sales tax he would pay 30% on those, or about $30,000 in tax. Even if he spends all his income he would pay no more than $60,000 in taxes. On the other hand a single mother making $20,000 is in the 10% bracket, and pays about $2000 in tax under the current system. Under a national sales tax though she would pay a sales tax of 30% on her purchases, which for her is usually the entire amount she makes, or about $6000. So in effect the doctor's taxes goes from $70,000 to $30,000 while the single mom goes from paying $2000 to $6000. Does anyone think that is fair? Well I don't.