Just imagine the expenses the NFL saves by having athletes provided by college programs. Sure, you can get a scholarship to play baseball, but when was the last time you saw a nationally televised college baseball game in the regular season. MLB and the minor league team owners aren't a big money maker, I imagine a majority of the teams lose money.
As far as athletes salaries, I have no problem with them getting whatever they can get, they generate a huge amount of revenue. The biggest problem is teams that are richer, from TV money, like the Yankees, often pay one player more than some of the smaller market teams pay the whole 25 man roster. But in most professional fields, the top 1000 or so in the field are going to be making as much or more than major league athletes, plus their careers can span as much as 40-50 years. I think I read once that something like 80% of MLB players that make it to the majors play less than 2 years. Often that is after playing baseball since they were 5 years old, with as much as ten years in the minor leagues. Out of that elite 1000-1200 MLB players, there are probably less than 70 making more than $10 million a year.
Also, I think of GA Tech, when it comes to college football, since I have only been to their games, and back in the 1920-1940 era, they used to be a dominant team, while having very high academic standards. This sort of predates lucrative pro football, so you had real engineers going to the Rose Bowl. I think it was in the late seventies that they changed their curriculum to add other degrees than engineering, and of course, this was with one thing in mind, to attract more athletes. Today, I recently read the Univ. of GA actually has a higher average SAT score among their students than GA Tech does. Sort of a bit of blasphemy.... Back in the early seventies, when my buddy was attending UGA, it was a big party school, I spent many weekends up there. It took him seven years to get his 4 year degree, and most of the photos that he posts or his friends from college post on facebook from the old days, he is visibly inebriated or high, today, he is a successful father and insurance salesman.