From the article, The Best Ways to Fix College Admissions Are Probably Illegal, by Jeffrey Selingo in The Atlantic:

“One effect of antitrust laws is that colleges in a weaker market position pursue strategies to generate revenue but that ultimately drive up prices across the board,” said Joseph Bagnoli Jr., the vice president for enrollment and dean of admission and financial aid at Grinnell College in Iowa. Those “strategies” he’s referring to are things like merit aid, or spending on amenities that competitors have on their campus, such as new dormitories and recreation centers. These amenities tend to siphon away money that could theoretically be put toward financial aid instead.