Education is expensive for the same reason everything is expensive: supply and demand. It is easy to inflate the demand for education with things like student loans and grants, but it is much more difficult to grow the supply of that education to match that demand. The infrastructure itself is expensive, then you have to worry about things like accreditation. You have way too many people that are academically challenged going to college because they were told that it was the only way they could succeed in life, when they really would be have been better served by something like community college or the trades.

As a result, you get kids with $150,000 in student debt at 7% interest with no job prospect to pay for it. The students made a bad decision, but Uncle Sam encouraged and enabled that decision.