Earlier quoted context omitted.
I'm pulling that amount from the cost of attending a school like Harvard (60k/year, not accounting for YOY tuition increases). The reason a lot more people don't do this is 1) irrationality when it comes to evaluating the brand of colleges, and 2) People don't tend to think in terms of opportunity costs, especially spread over 4 years (which is what the 240k represents).
It may cost that much, but you couldn't get that $240k in cash otherwise. Either your parents are paying the $240k or your taking loans or some combination thereof. How do you get a $240k loan if you are not studying at Harvard or a similar school?
The $240k could be realized through a varying mix of: not having debt (and having to drain off 240k + interest in future income), not spending money you earned working over the summer/part-time (this won't cover it all, though), and/or a your parents giving you the college fund. Regarding the point about the parents, I readily acknowledge that not all parents would be willing to do that, but many probably (in my opinion) would.