Still, though, people are loyal to the institutions that sustain them... often unconsciously, and often via earlier filtering/selection.

There's no need to assume Ariely is under explicit workplace pressure to promote elite universities, or that he's hustling for the incremental gain to his status or income. It's enough to recognize that someone who's the son of a Columbia MBA, a graduate of Tel Aviv University and a holder of doctorates from both UNC and Duke, and a professor at MIT and Duke, has already been massively selected and rewarded for his deep-seated faith (and ability to thrive) in those sorts of institutions. His intimate familiarity with the system gives his testimony credibility, but his career involvement also makes it unlikely he'd say, "it's just not worth it".

So I'm not even particularly saying that he's wrong, just that his formally-titled, well-remunerated, large-sunk-cost and choice-supportive-bias position inside the high-tuition private-university system is relevant enough to warrant a mention, if he's giving cost/benefit advice to others.