There is no sales tax in my state, so frankly, I am not open to the idea of paying sales tax to purchase something, nor of charging it against anyone who buys something from within my state, regardless of where they come from. I've bought large ticket items in Washington, and been exempted from paying sales tax on them because of my Oregon residency. Its good for me, as I don't have to pay someone else's tax, and its good for them, as they get my business when they absolutely would not have otherwise.
I don't care in the slightest where anyones physical location happens to be. But if I happen to want to buy a tennis racket from a merchant in a sales tax state, I don't think its unreasonable to pay their tax. On the other hand, if they buy something from a merchant in my state, they damn well better not be getting taxed for it.
That said, Amazon and whoever else should be welcome to set up shop here (and in other no-tax states) and sell to the rest of the country tax free.
It shouldn't matter where the customer is located, only where the business they are buying from has a physical presence.