Here publishers are marketing to professors who assign particular textbooks and subverting students which are the actual market and consumers of those textbooks. This causes an inflated market and has allowed textbook prices to spiral out of control.
The American Health Care Market
In this example, the health care providers (doctors, hospitals, etc.) have been segmented away from their consumers (patients) by intermediary insurance companies which are driving the market to their own good rather than a free-er set of smaller (and importantly local) markets that would be composed of just the sellers and the buyers. As a result, the consumer of health care has no ability to put a particular price on what they’re receiving (and typically they rarely ever ask, even more so when they have insurance). This type of economic anomie is causing terrific havoc within the area.
(Aside: while the majority of health care markets is very small in size (by distance), I will submit that the advent of medical tourism does a bit to widen potential markets, but this segment of the market is tiny and very privileged in comparison.)
In a non-economic setting it also seems to be highly applicable to social media silos like Facebook, Twitter, et al as they break social norms. I’ll have to circle back to write a longer essay about this with regard to the IndieWeb movement.