One way of getting around the rule is to have a customer take delivery of the car and right away trade it right back, as the car is titled it becomes used and it's fair game for the markup.

Fo years the local Ferrari dealer have been doing this, I heard Ferrari got wind of this and took away the franchise.
It has gotten so bad that the dealer is paying people to take delivery of their ordered cars even if the customer changed their mind and want something else. $5k-$10k is not unheard of.