Student loans had to be a top answer. The fact that they even call loans "student aid" is bonkers. There were two events with student loans that really drove that home for me.

First, there was a school I was considering applying to that advertised that they would pay 100% of what the government determined was your family's need. They had 2 admission windows, one "early-decision" with a good chance of getting in, that was before when the govt releases their estimates of your need, and another with abysmal acceptance rates, but after you'd know the cost. For someone without money, you would have to give them a binding agreement to go there if accepted without knowing what you will end up paying, or you likely wouldn't be accepted at all. I ended up not applying, but if I had, I could have attended a good school for around $3,000 per year, including room and board.

Second, one year i was in college, my parents (who weren't paying for any of my education) made less money. This made the government offer me higher loans. Because I could get more "student aid" from the government (loans), my school reduced my scholarships.