The Ph.D. program, in our times at least, is pitched as a quid pro quo: you produce some original research, something worthwhile and of substance, to add to the sum of human knowledge, and in exchange they gain access to an academic career.

Anecdotal rebuttal: The first conversation I had with my research advisor concerned the difficulty of getting a tenure track position at a research university straight out of Ph. D. school. In her words, "that sort of thing just doesn't really happen anymore in this field (Computer Science)."

There are no delusions of academic grandeur, at least in my neck of the woods. I agree that the Ph.D. may be pursued as a career maneuver, but if your end game is a teaching position at a research university your approach to the program has to be very different (and extremely more ambitious) than someone pursuing industry or other goals. And if you're pursuing a prestigious academic position, you are quickly educated on the slim possibility of attaining it, even if you're willing to post doc.