because it depends on the person himself, if he is up to collecting affiliates or not. because if you are an introvert person, you won't waste your time looking for others to be your affiliate. you are just happy playing on your own.
I think you may have misconception about the subject of affiliate and how it works, because playing on your own doesn't have anything to do with your affiliate program if you subceibeyto any of them and as a matter of fact affiliate program is all about the earning and not the games you enjoy playing.