NOTE: I am not agreeing with this practice, but i understand why it is the way it is.

So, as an academic researcher, i know a bit about these things. Ok, so most research is funded via government agencies, and the majority of work that goes into publishing papers is done by PhD students. This money is going into paying for them to live, they receive a paycheck, its going into ordering lab supplies so the work can be carried out. Without this funding, nothing would be possible. And at the end of the day (or at the end of 5-6 years!) those PhD students graduate, and now have access to many high paying jobs, which once again without the governments funding they would never have done the work required to get the degree. Guess what; If the government gave your lab group a boatload of money, and you turned it into 4-5 prestigious publications in "Nature" or whatever, congrats, you can now get that professorship you've always dreamed of, and once again you lived your life doing this entirely on the governments dime. So of course they feel its right for them to get money in return. As much as we want "public goodwill" to be a thing, these agencies arent unlimited money-trees, they dont have an unlimited share of our tax dollars, they want to keep themselves up and running so they can continue to fund projects that will be useful to society.

Also, If you have an original idea, and want to profit off of it, you certainly can. There is no one telling you that you cant drop out of your program and develop your idea, patent it, and reap the benefits if it succeeds. But this is a high risk, high reward situation. Government funded research projects are low risk, still pretty high reward.