A senior software engineer at Google has a base salary of $162,000.00 a year. He will also be able to do that job until he's 65 or so, most likely moving up significantly over the years in position and salary. Humphries most likely won't be playing professional basketball on any level in 5 to 10 years. And there's a decent chance he never makes $150,000.00 a year.
It's also cute that you think these guys who are leaving early are going to get their degrees, save, and invest wisely. lol. Maybe 1 in 20 will do that.
There is value in playing basketball for four years at Kentucky. Plenty of guys have been milking BBN's big tit for decades. Good luck doing that when you were a forgettable 9th man for two forgettable years. I'm sure it's hard to turn down an $85,000.00 salary from the Saudi Arabian Dust Ferrets, but the better retirement package involves lounge singing for Kentucky fans, not driving a taxi in Riyadh.