As with any law, you get one or two smart people writing it, but you get 1,000,000 people trying to figure a way around it, and eventually odds are that someone will, then everyone copies. Car dealers have a 'holdback'. There is MSRP, then there is 'Dealer Cost' that is printed on the receipt to the dealer, but then there is a bonus the manufacturer pays the dealer of maybe $ 2,000 per vehicle sold at the end of the month. This way, a hard bargaining customer might be proud that he negotiated a price only $100 above dealer cost, but the dealer still made $2,100 on the sale.
So how about doing that backwards: Lotus UK sells an Emira to Lotus USA for $ 100 that is subject to $25 tariff, but they charge Lotus USA $99,900 licensing fee per car for using the trademark name 'Lotus' ....