But you ignore financial aid (most people who have to borrow every cent will qualify for some at at least one school they apply to), term time employment, and summer jobs/internships.
If you absolutely can't get any financial aid (i.e. wealthy parents who won't pay for you but whose income prevents you from aid eligibility), then you are simply an idiot for not getting a job shelving books in the library and pursuing paying positions in the summers.
Term time employment is not hard to find (and in my experience, campus jobs tend to pay on the high side), and you can find something that is only 10-20 hours a week and won't interfere much with your studies. Also, half of the student jobs out there are the kind where you can study in your down time (the kids who check out books at the library or ring you up at the student coffee shop can spend half of their time doing their course reading). At $12 an hour (pretty common for student jobs, even without work-study), this can net you 6-7k each year. And of course you could always work more if you really needed to (and reduce living expenses below the "average" which includes the kids living off mom and dad).
Then, you should absolutely be working during the off periods. Not too hard to nab a retail job during winter break leading up to christmas (although not a ton of earnings from that either). But you should be working full time all summer, every summer. Even if you don't need the money, you should do this since it always seems like the kids who don't are the ones who have the hardest time finding jobs after graduation (no experience). Even if you can't beat the $12 an hour you had before, this should get you another 6k for the year. And after the first year of school, you get access to better programs, and internships from higher paying employers. Lots of places pay interns the same as 1st year employees...even in the middle of the crisis in the summer of 2008, lots of kids were getting an easy 15-18 an hour plus overtime. With a bit of work, its not that hard to clear 10k in a summer. Yeah--you don't get to go take that unpaid internship that the rich kids can afford, but it's ok--they are just being exploited anyways. You'll come out with experience, money, and maybe even a post-graduation job offer.
That pretty much covers all of your living expenses (and then some...considering you should probably be living a little sparser than the average student). Honestly, you could even still drop a grand in extra loan money on a cool spring break every year and it wouldn't really matter. You are still going to clock in at only mid 5-figure debt.
The people complaining in the media about 150k debt for 4 years of school are either lying, actually had post-graduate education, or made extremely poor and lazy decisions (and I count going to a $$$ private university as a poor decision if you have zero financial aid). Its not even easy to get 150k in loans. You can't get that much from federal loans...and private lenders aren't so favorable to slacker kids who can't even bother to earn a single dollar all 4 years.