Some colleges teach you to think, some don't. A 'classic' liberal arts education starts with debate, discussion, and rigor. An engineering school starts with terminology, overviews (survey classes), and specialization options. Learning to think takes both an institution willing to teach it and a student willing to learn it.

However, it seems that a number of people, possibly more than half, under-estimate the value of learning how to motivate yourself to finish things in the presence of losing interest in doing so. Lots of people "get" the joke that the last 10% of a project takes 90% of the effort but they don't get the fact that folks who never learned how to motivate themselves through the finish (of which having a college degree is a reasonable signal) will 'drop out' at the 90% point at best, and become dead weight at worst.

Combine that with the unemployment statistics of folks with versus those without college degrees and statistically it seems you want to be in the 'with' group.

The bottom line is that college is the first place you get to show the world your work ethic and your 'mettle.' That's because for many its the first place where not-going is considered a legitimate option.

You can be very successful without finishing college, see Bill Gates or Steve Jobs as examples, just like you can get into the National Football League or Major League Baseball by going to open tryouts. If your personality is suited to that, its going to be a great option for you. But success on those roads isn't the "more common" outcome.