I know people who've worked in admissions at a surprisingly large number of colleges-- private and public, universities and liberal arts colleges, elite and average-- and they've all indicated the importance of yield.
Names of the colleges, please? The great majority of colleges have yields well below 50 percent,
http://talk.collegeconfidential.com/college-search-selection...
so the great majority of colleges are already accustomed to admitting a majority of students who will NOT enroll at one of the colleges that admitted them.
Your comment would be much more informative if we had some idea exactly which colleges you are talking about, and which persons affiliated with each college you have spoke to, and how recently.