To be fair, our dad drove like this on American highways each and every summer vacation.
Now picture this madness, but with someone driving in the opposite direction into oncoming traffic. On purpose. That's a geisterfahrer.
Why would anyone do something so objectively insane? Well, some ghost drivers do it for nothing more than the lulz, bruh. Others are straight-up suicidal, such as the ghost driver who very nearly vehicularly manslaughtered the governor of Bavaria. In all honesty, this was a very Bavarian thing to do.
Of course, the German government couldn't officially have the world thinking that their highways are haunted by a bunch of reckless ghost motorists, so they decided to try and come up with a different name: falschfahrer, or "wrong drivers." This is admittedly a much less frightening phrase, but when you're trying to convey to tourists that your supersonic roadway is occasionally plagued by maniacs trying to cause head-on collisions at hundreds of miles an hour, maybe frightening is what you want.