Note that $8,500-$10,000 per year is the high end of expected student contributions at colleges with good financial aid for high-need students (some of the best-financial-aid schools have lower expected student contributions, like $4,000-$5,000 or so). So high-need students at colleges with good financial aid are expected to “work [and perhaps borrow with federal direct loans] their way through college” up to about that amount.
But if the parents are higher income (i.e. resulting in less or no financial aid), but do not contribute (note that allowing the student to continue to live at home for free is contributing), then the student will find it very difficult to “work his/her way through college” without starting with a large merit scholarship. The same applies to students who do not get into good-financial-aid colleges. If the parents will contribute by allowing the student to live at home, but not otherwise, then a student in this situation who lives near low cost community colleges and in-state public universities may have that option to “work his/her way through college”.
But such options are less numerous than a generation ago, when a student with no support from parents, living on his/her own, may have been much more likely to be able to “work his/her way through college” at any in-state public university.