Really? Now I realise why some Americans looked so confused and dismayed when I was living there without having ever learned to drive.
So there's nobody from USA who chooses to have an education, and not to drive a car?
HS graduation requirements vary (in some cases, much more than you would think) between districts. Usually, each town/city has its own district -- in rural areas a district may span many towns, in more urban areas, you may have more than one district in a single city. There are state guidelines, but we also have 50 different states. Federal guidelines are pretty sparse, and often only enforced by accepting funding -- don't take their money and you don't have to play by their rules.
I suspect that there is no blanket statement about the US public school system that will hold true nationwide (except, perhaps "it could be better" or "it makes no sense").
The reaction to not having a license is probably simply due to 60+ years of "The American Dream" for a kid was having their own car and the freedom^tm that came with it, and the simple fact that in the majority of the country, public transportation is crap, and our cities are not designed around walking. So a car, and license, is pretty much a requirement.
A lot of people would argue this is very good policy.
Given that most students do get a drivers license, it wouldn't be surprising if Drivers Ed were a mandatory part of some high school curricula. Note that this is probably just the theory part in most cases and doesn't include actual on the road instruction. (Which is typically done by parents or by a company--the latter again in part for insurance price reasons.)