Exactly. Universities sell credentials, not knowledge. If universities actually did sell knowledge, they would have been put out of business by public libraries long ago.
This is true if you're saying that universities sell credentials among other things but false if you're implying that universities _only_ sell credentials. They also sell a rich learning and networking environment; _structured_ knowledge that you're presumably acquiring from people who've already mastered a field and thus can bring you through it faster than you could on your own; motivation in the form of deadlines and so forth, which is often difficult for most people; editing / mentoring relationships that help you dialectically develop your skills; and a way to guide figuring out what you might be interested in.
None of that is to deny that universities sell credentials too, but if that were their only function, they wouldn't be essential to our society.
> They also sell a rich learning and networking environment ...
That is worth anything only if it will help achieve future profesional goals. You are probably thinging of a rich start-up culture. It can be awesome for engineering and business majors. But for humanities, I am not so sure.
> motivation in the form of deadlines and so forth, which is often difficult for most people;
There is some value in that. Universities used to play the 'in loco parentis' role in the past (http://en.wikipedia.org/wiki/In_loco_parentis). In other words they provide an environment where discipline and certain norms are enforced. I am just not so sure it is worth $120k worth of debt at the end.
Could point. Therefore the diploma mill market. All in all it is just another bubble. The only thing that keeps the bubble going is that employers still screen based on degrees, therefore degrees are perceived to have value. Now I would argue for not even working for any employers that screen heavily based on degrees instead of extensively checking and matching a candidate's knowledge and personality fitness ... but that's just me.
> ... they would have been put out of business by public libraries long ago.
And a lot of universities already publish quality course materials on the web.
Uh, aren't we talking about the people who don't get jobs from their degree? Seems unlikely that such people care a lot about a brand name they won't use.