Did I say that was the only answer? Absolutely not. But you're talking as if every single person out there has the ability to go to college if they want to and that's simply not true at all. You list these dollar figures as if every person in America can afford it and that is also not true. You act as if the only thing a student has to worry about when they get into college is the tuition, and again, NOT TRUE.
You go ask a kid who has no choice but to live in a very poor, urbanized city where crime is high and the average income per household is under $25K a year. Where people have to REALLY worry about getting home safely, finding food to eat, paying the necessary bills to survive day to day and keeping a roof over their head. Sure, they may think about college. But to these people, even a state college at $3000 a semester is too much to afford!
Of course, the only excuse you have for these people is that they don't have parents who care enough that their kids get the proper education. Such an easy, over-simplified answer for those who essentially "got theirs" and don't give a damn if anyone else "gets some".
Like this makes a difference? It doesn't matter if you had two parents who didn't finish school. They still had you and made sure to enforce the importance of an education. And despite the dire situations you may have been raised around, you were able to keep focus and do what was right for you. Consider yourself one of the lucky ones. All I'm saying is that
many parents would love to see their kids got a proper education and went to college, but feel as if their child's immediate safety and survival is more important. It's not as if they completely ignore or disregard the importance of an education (as you imply), but it would be even harder for a kid to go to school or even college if they didn't have a place to live.
Every case is different, but I'm sure if you went down the line of parents who had children who didn't go to college or dropped out of school, you'd find that there were MANY other answers besides not caring.