Well Michael Russell apparently recently got his BS from the University of Phoenix...
I don't think Kosakowski will be living in his parents' basement. Unless his arm falls off or something he should always be able to make a decent living from tennis in one form or another. So I don't blame him for putting college on hold.
Well, you can be a ball feeder giving lessons to housewives and beginners (that's where the majority of the players are in tennis) for the rest of your life, or you be Director of Tennis at a club, for instance. That takes knowledge of finance, marketing, business...all skills that they typically require a college degree for.
Which one makes more sense in the long run?
I know of a former pro that finished at Stanford and retired a couple of years ago to a very good professional job paying 6 figures plus.
Not going to be able to do that when the money runs out in 2-3 years and he's faced with either paying for college or giving lessons for the rest of his life.