Green means go

Am I the only one that knows there are stop light sensors in the road?
People that stop at a red light, 6 car lengths back from the light, drive me nuts.. I realize that not every stop light in Danville has underground sensors.. But a big majority of them do..
What does this mean? It means that if you stop your car on top of this thing, it sends a signal to the traffic light that says "hey traffic light, change colors".. If you stop your car before it's on top of this high tech mechanism, the traffic light never knows you're there.. Nor does it know know the 20 cars behind you are there.