How in the world is it even possible for a person to collect sales taxes based on every town in the country?
Leaving the ethics of it aside, the computer age has made that quite possible. It would be extremely easy to build a type of cash register that would immediately determine, assess, and send taxes off to every taxing authority covered by a person's nine-digit zip code. Chances are, it would be imbedded in your next credit and/or debit card, you won't even have to tell them where you live.
Big Brother will indeed be watching everything you and I do commercially, we just needed enough politicians with the will to decree it. Tax money is usually enough of a justification.
Simple. One flat Federal sales tax.