So it becomes a brand-name game. You pay for the brand, you spend some time getting indoctrinated (most likely to how important this particular brand is) and you get your piece of paper.
Somebody said once that the purpose of education is to create new habits. So, for instance, if you are an English speaker and develop a habit of reading a good Russian novel once a year, that might be an excellent habit to have. Or if you develop a habit of reading a dozen computer books a year, or perhaps you develop a habit of cross-checking politically-slanted stories you agree with. And so on.
Lots of great habits that you can form. Some subset of these constitute what we call "critical thinking," which everybody seems to think is important. There are a bunch of entrepreneurial habits that I'd love to make sure folks had. If you want a job after college, developing great people, marketing, and networking habits would be awesome.
But I don't think anybody wants to seriously start talking about what habits college graduates should mostly exhibit. To do that would cause controversy. Colleges are very much dependent on public dollars (at least in the states) and I don't think they are ready for the political firestorm that would occur once you start actually trying to define the thing that we're all paying for.
It's not a bubble, except for the part about more and more money goes for less and less return. The problem is that there is no "thing" that is being returned. There's no bad guys here, but it's much more like a con: you pay increasing amounts of money for this intangible thing where there's no real way to determine if what you got was what you wanted. You don't really know if it's worth what you spent, because the seller is purposely keeping you in the dark about the value, continuing to assure you that this type of purchase at these rates is absolutely necessary. In fact, as time goes on they get more and more insistent that this thing is absolutely necessary -- at any price.
That kind of building up of expectations, then jacking the price, then delivery of something that could roughly be considered what was needed but isn't enough, repeat-and-rinse, is much more indicative of a con (Disclaimer: I don't mean to imply intent here, and I also don't mean to imply outright fraud. Just trying to find the best metaphor. I also realize that I am making a large generalization, and all generalizations are false. Caveat Emptor.)