I know it was how the engine spawned vehicles in gta4. I didn't like looking behind to see the cops chasing me only to look forwards and rear end traffic because it spawned while i was looking back.
Idk about pc but the 360 and ps3 are guilty of this. I know it's how they get traffic to spawn as you're turning a street corner. Just annoying to crash into the back of a car that want there before.