And that is probably because Willow Springs doesn't have a lot of vertical surfaces around the track. Headlights are bad at making the actual road visible, since the roads runs more or less parallell to your line of sight (a property that increases with the distance), and as such the road surface reflects very little light back to your eyes.
Roughly speaking, if the driver's eyes are 1.5 meters above the road and the road is perfectly flat, a vertical object 30 meters away, of the same material as the road, will appear 20 times brighter than the road at the same distance. The greater the distance, the greater the difference (although at some point the road will just appear black and from then on the apparent difference will decrease).
