If AWD is automatically inferior to RWD for track stuff, and its only advantage is rallying, why do cars such as the Audi R8, Audi RS4, Lamborghini Gallardo Superlegga, Nissan Skyline GT-R, Bugatti Veyron, Porsche 911 Turbo, etc come with AWD? None of these are rally cars.
There are advantages to RWD on the track, and there are advantages to AWD. I don't think you can say that one is always better than the other. I think it's really more of a preference and driving style thing.
In Porsche's case at least, how come all their most track-focused cars are RWD? GT2, GT3, Carerra GT. Even the Cayman. All the cars you've mentioned post rapid lap times due to monsterous power, not remarkable handling.
That's fine, I'll drop the Porsche and the Bugatti from the list. That leaves the Audi R8, the Audi RS4, the Nissan Skyline GT-R, and the Lamborghini Gallardo Superlegga. All of these are meant to be fast around a racetrack, and none are ever meant to go off-road. These are all cars where, if the manufacturers wanted to, they easily could make them RWD (they have longitudinal crankshafts). Did Audi do this with the R8 because it
wanted the car to be second-best to RWD cars? How about Nissan with the Skyline GT-R? Of course not. They did it because some people prefer AWD over RWD, even in a dedicated performance machine. Other companies offer RWD instead of AWD because other people prefer RWD over AWD in a dedicated performance machine.
Like I said, it's simply a matter of personal preference, kind of like forced induction versus naturally-aspirated engines.