
RickJay allready touched on it when he pointed out:
… (For Canadians, that’s how our GST works. Businesses pay full GST for everything they buy, with a few exceptions, and deduct that from the GST they charged on what they sold, and then pay the difference, if there is one.) A national sales tax would almost certainly be VAT-based.
The key phrase there is *and then pay the difference, if there is one.**. This is the same way it works in Sweden as well, by the way; I cant speak for other european countries.
In VAT systems, the VAT is paid by the manufacturer. The manufacturer has allready done the calculations vis a vis VAT and profit margins when they determine pricing - VAT rebates based on pricing vs. VAT expenditure to suppliers is built into profit projections to shareholders. Especially in businesses with a lot of competition and/or slim profit margins, this very practically limits the ability to respond to price wars, or to start them for the purpose of gaining market share, or to get rid of excess inventory, etc. The projected share of the market one gains from a price war would need need to be higher in order to justify the temporary loss in less VAT rebates recouped.
This is (partly) why europeans dont see the same level of Factory Rebate Sales as we do here in the US, or weekends where everything is 50% off, or “prices slashed, everything must go” - because the manufacturers have allready paid a certain level of VAT to their suppliers, and need to recoup a certain amount to avoid having to pay an unnecessary amount of taxation. It can and does happen, but the sale or rebate must needs almost guarentee a large enough increase in long term volume/market share to justify the short term cost in extra VAT paid (or not rebated as the case may be). Some businesses may actually prefer this, but thats not the same as saying its good for consumers.
As for a national sales tax, I have no problem with it. Nor do I have a problem with a flat tax (though I would prefer the flat tax). But then I cant understand why its just taken for granted that poor people shouldnt have to pay taxes. What, they arent protected by the same military, police and fire depts? They dont drive on the same roads, use the same infrastructure? I know when I was dirt poor (which has been most of my life), I used the same public services I use now, in the same amount. Why I have to pay for them now but I didnt then, Ive no idea.
Questioning the logic behind the progressive tax system feels like questioning the existance of God in 16th century Spain. It really boils down to nothing more than a belief; much like marriage is only between a man and a woman.