40% of the players in the US Army All Star game were from the South (that was the only year I counted). In fact, there were so many southern players that Louisiana had to be counted as West in order to make room for the rest of the players in the Eastern United States. Considering that the UA All Star game is almost all Southeastern players, and the other main All Star game has more players from the Southeast than any other region I believe it is pretty obvious which region of the country produces the best athletes.
So basically, out of the small selection of Southeastern players that the US Army All American game gets to select from because of the strong competition they face from the UA game they still fill out almost half of their players from the Southeast.
So, yes, the games choose the best players...and these players are from the Southeast.