The racing world is part of the sporting world, but not all race are done legally. Most are done on the streets and can only be done at night because it is secret. For those, who compete in a legal race, the road is much safer and the price are much higher since there are many sponsors. The car that got first place gets the biggest share of the price and that is why, every participant want to be the first to cross the line.
Drive your car as fast as possible. Try to evade other cars, so it won't slow you down. use some booster to get ahead of the rest. You will earn some money based on the placing of your car in the race. You can use the money to upgrade your car.