Let's see if I understood you well: you mean that the winner of drift races gets not only the 1st prize money, but also the same amount of dollars as drift points he has got in the race, right? And is that a bug??
Isn't it made that way on purpose? And of course it shouldn't be removed because that is an extra incentive for people to join races (which is exactly what they need nowadays that very few people join them). Actually there should be money given by the system to the racers for more people to join races without the hoster spending lots of cash.