If you compare the long-term earnings, lets say over 50 years, of taking all the money that would have been spent on college, and especially if you add private school tuition to that (which many parents would in order to get into a good college in the first place), depending on the exact numbers college can be an outright losing proposition.
Some quick examples for investing your school tuition:
$300,000 at 5% interest invested at 22 == $3,440,219.94 at age 62.
$10,000 average private school tuition invested each year from 6 to 18 + $100,000 college tuition invested at 18, 5% interest rate == $6,472,837.02 at 62
vs
$10,000 avg invested annually starting at 22, 5% interest == $2,312,827.95 at 62
$20,000 avg invested annually starting at 22, 5% interest == $4,625,655.91 at 62
Of course there's lots of ways to play with the numbers, and other considerations to take into account. Do you really, really want a specific career that requires a college degree, or do you just want a middle-class lifestyle? Is that career goal realistic, or will you just end up another depressed burnout? Plus most graduates won't be able to invest $20,000 per year starting at 22, that's highly optimistic, and most people who don't go to college won't have absolutely zero lifetime earnings either.
The opportunity cost of time spent attending schools you don't enjoy versus doing other things with the "best years of your life" is another factor, too.