Now is this cartridge strictly for benchrest or does anyone hunt/varmint with it?
You certainly could, but I can't see why you would want to. The PPC is about as slow as you can get in a 6mm cartridge, about 500 FPS slower than the .243 Win in any given bullet weight.
It may be one of the most inherently accurate cartridges, but in reality that isn't needed in a hunting or varmint rifle. From the field not many people would be able to tell the difference between a 1/4 MOA and a 3/4 MOA rifle.
PPC chambered rifles are pretty much custom only (aside from the Sako and Ruger mentioned above), if you were wanting to build a custom varmint rig, there are better choices in cartridges, if you were building a custom benchrest rig, you probably wouldn't want to use up your finite barrel life blasting P-Dogs.
Never say never though, I am sure at some point someone built a 6MM PPC hunting rifle.