The original incentive programs gave away a lot more cars. Bjorn won both an X Founder's series and a fully loaded P90DL through those. Though it will probably be delivered as a P100DL.
In the more recent incentive programs they have just given away one car by a drawing. They probably started doing the drawing because the same people would end up winning many cars if they stuck with the old contest conditions. Plus the new conditions are a lot cheaper for Tesla.