Fuel costs at the pump in Europe are often easily 2x the price we pay in the USA which is one reason why our roads and bridges are falling apart! The actual costs of the raw materials is similar as is the refining of it between the USA and most of Europe.
Where I live in New Hampshire, we do not pay a sales tax on general merchandise at all (you do in a restaurant, hotel, but when you register your vehicle, you pay an annual tax to the state/county/city where you live based on the value of the vehicle - sort of a personal property tax. To get your tags renewed, you pay the state, and that is based on the weight/type of vehicle. Those fees are miniscule compared to what amounts to a personal property tax (which decreases every year). It still works out FAR less than the typical VAT most of Europe pays for their vehicles and merchandise (US is about 3%, built into the price of the car by the importer). The difference between VAT and the US import fees is one reason a why cars are a lot cheaper here than in Europe, even counting the extra shipping costs.
Each state has their own method and rates of sales taxes and registration fees and there is no federal fee as a line item either during or after the sale of the vehicle - the importer includes that in the base price of the vehicle. Well, there is one exception - depending on the fuel efficiency, a vehicle might be subject to a one-time fuel guzzler tax by the feds, but that certainly does not apply to the i3! The majority of vehicles sold here do not get hit with that fee, and if it does apply, it's paid to the dealer when purchasing the vehicle.
FOr now, there is a $7500 federal tax credit on the i3 for the first purchaser of an i3. Note, not everyone will see the full amount based on their taxes and income...you won't get the full credit if you haven't paid that much in based on the rules when filing your taxes...it's not a rebate. Some states do have rebates on EV purchases (mine doesn't), and that's cash back into your pocket.
There has been some discussions about applying a certain amount/mile driven verses x amount per gallon of fuel purchased to account for the fact that newer cars get much greater fuel efficiency than older ones, so the actual road wear and tear is no longer equitable, especially with EV's not paying anything because they don't buy gasoline. That issue will becoming more pressing once more EVs are on the road, but it makes sense for the existing ICE vehicles as well. Administering it, though, would add another bureaucracy that most people would like to avoid as well as the periodic bills.
2011 535i x-drive GT, 2014 i3 BEV