Tifton KOA? I was there a couple of weeks ago.southern GA from upstate NY sold propane, and yes, one of them was a KOA.
Of all the full hookup campgrounds I stayed in during this trip (more than usual), the only other one I can recall that sold propane was the KOA in Kingman, AZ. I think KOAs all have the same stuff, TV Cable, propane that most others do not have.
But I assume you find more propane places in the north, such as in NY.
-Don- Ft. Stockton, TX