The Tamar Lewin story in Wednesday's (9/21/11) New York Times provides more detail than you get in the NYT blog post linked in the OP^^; you can find a link to the longer story in the blog entry.
I don't know if I'd describe full-pay as a "hook," exactly. It may be at some colleges, but not at those that profess to be "need-blind" in admissions, which includes most of the most-selective colleges. So for the most part colleges that are now going out of their way to find full-pays are colleges that are somewhat easier to get into anyway---and not the colleges where the typical CC reader is most eager to find a "hook."
It also seems that much of what's described in the article isn't predicated upon using the individual applicant's financial data as an admission criterion. "More than half of the admissions officers at public research universities and more than a third at four-year colleges said that they had been working harder in the past year to recruit students who need no financial aid and can pay full price," according to the article. OK, that's a lot. But only "22 percent of the admissions officials at four-year institutions said the financial downtown had led them to pay more attention in their decision to applicants' ability to pay."
At first glance those numbers don't seem to add up. Which is it, 22% or more than a third? Well, here's the answer: "Admissions directors at many public universities said in the survey that recruiting more out-of-state and international students, who pay higher tuition, was their top strategy."
Public universities don't need to be "need-aware" on an individual applicant basis in order to improve the school's bottom line. They just need to admit a higher percentage of OOS and international students. Not only do the OOS and international student pay a higher tuition---in some cases 2 to 3 times as much as in-state students---but they tend to be self-selecting by ability to pay. That's because most public universities do not promise to meet 100% of need for OOS and international students. Some don't give any need-based aid to OOS or internationals. So the OOS and international students who accept the offer of admission will skew heavily toward full-pays; most of those who can't afford the full sticker price will find a more attractive offer elsewhere. A few may self-finance by taking on large debt loads, and that's where the university needs to be careful because it could increase the attrition rate (and decrease the graduation rate).
Is that a "hook"? I wouldn't describe it as one. But it is the cold, hard reality of today's higher education market.
Also interesting in the Tamar Lewin story: some (an undisclosed number of) admission officials acknowledged admitting men with weaker credentials so as to preserve gender balance. I never thought it would come to affirmative action for males, but apparently that's now the case at some schools.