If you think BMW is paying import tax or duties for the X5 into the EU, you are wrong. According to european laws, there is no duty on cars or machines which are assembled overseas with parts already produced in the EU. The main components have to be produced in the EU, as it is for the X5 the engine , gear box, and other stuff coming out of Germany and Austria.... BMW is earning money on the on the X5 in Europe, they nearly spend money with every X5 in the US as the price level is quite low due to the exchange rate.
BTW you have to pay tax and duties if you import an X5 on your own, only the manufacturer is allowed to do this without duties....
So long
Christian