The correct solution isn't to raise the misery on people that shop at Amazon - rather, it is to decrease the misery for people shopping at Barnes and Nobles. In other words, don't increase the misery by raising taxes on some shoppers - increase the pleasure instead by lowering taxes on some shoppers.
The less money the government can steal from the people, the better off we all are.
If you don’t like sales taxes, go to your representatives in your state and get them to repeal the sales taxes.
But government does need SOME money to operate, and they have to get it from the citizens somehow. If not a sales tax, then an income tax, or a property tax, or a gas tax, or some other tax.
If there is going to be a sales tax, it should apply to like goods no matter where they are purchased, otherwise there is a disparity in misery.