| I think the relevant difference is that VAT is paid even if you are in a different EU country. I'm in Denmark, where the rate is 25%. I pay 25% on something I order from a Danish online shop. I pay 25% on something I order from a large German online shop, even though the VAT rate in Germany is lower. I pay 19% (the German rate) on something I order from a small German shop, to reduce the administrative burden on that shop. (In every case the advertised price includes VAT, although the middle case may use 19% until I input a delivery address, depending on how they guess my location.) My understanding is that, in reality, people pay 0% in the USA if they order from a different state. |
The key here is that when something is classified as "interstate commerce" different laws apply than if you're buying something in-state. Enforcement varies, and can be expensive, and the laws are catching up sometimes, and purposefully not present in others, depending on the state and their approach to interestate commerce.
As an American, I'm quite happy there is no Federal sales tax. There is no reason to capture value at that level and allocate at the Federal level. States already have these taxes, and are much better equipped (in terms of need / proximity - not in terms of functioning government at times) to allocate the money toward local services.