Because as a driver you have to be seed 5 to get your initial pro license. as a co driver you must have finished four co 2 or 3 clubs to get a pro license. Not every one can get a pro license at the begining of the season. It use to be you could start the season club and if you moved up you could upgrade your license mid season and get you club fee credited towards your Pro fees. I cant think of any reason to have both.