Sure, I'll give you some reasons:
1. They already make money. It's called FREE COLLEGE (which includes tuition, room, board, books, supplies, computer, insurance, snacks, etc), along with FREE training from some of the best trainers available. In addition, they are now getting a stipend of about $4k per year for "run around" money.
2. Having a few "highly" paid individuals on a team would destroy the team and therefore destroy the sport. My guess (yes, my guess) is that those few athletes complaining are the ones with the lowest potential earnings. The couple of dozen that may make some money are probably working hard to prepare for their futures.
3. If any particular player is so valuable in the market place then they should leave school and enter the market. Nothing is stopping them from doing so today. Oh, a don't give me the 3 years after HS thing that the NFL enforces. If they are so valuable in the market, go to the market and wait until they are eligible. No problem.
4. People like me pay the bills because we enjoy watching college student/athletes compete and do well. If they start paying large sums I'll stop watching those teams altogether. I'm sure most other college fans would as well because that wouldn't be "college" but instead would be professional. I don't like actual pro sports much now and I really wouldn't like the half-ass version of college pro sports.
5. Because people like you with no vision or knowledge of history push your BS down everyone's throat without a single thought that there may be another side and that other side may just in fact be better than your agenda.