I see this failing quickly for one big reason...internet sales. Even the most liberal of people likes to use Amazon to fnd the best deal on their goods, rather than having to drive all the way to Wally World to buy it themselves.
Seriously, if you add sales tax and shipping to a purchase, the benefit of Amazon and other internet sales vanishes quickly. Watch who yells about it this time (I hope, unless they're too busy watching the new Bear Grylls show).