The constitutional ban on sales tax is about the only good thing about living in Oregon. Though sales tax is *entirely* regressive, so kind of amazing it flies in the state that gave us Branch Dildonians, Stormfront and kept putting anti-GLBT measures on the ballot for decades.
In Europe we just include the sales tax in the price on the shelf. If the label says £1, I hand over £1. When I'm buying something I don't really care how much of that £1 is tax, how much is going to the shop, how much is going to the producer etc.