The crux of the claim is that the schools "overcharged" students by admitting students who could afford to pay more, instead of rejecting those students and admitting different, poorer students. So the only people actually harmed are students who did NOT attend these schools, and paid more at a different school. That's not who the plaintiffs are.

Essentially, wealthy students (who were admitted!) are claiming that they could have gotten better aid packages if the schools set prices based on something other than need, and competed for the value those students brought to the school. Since the schools allegedly endeavor to hit a target total revenue, while charging less in tuition than the cost of providing the education, the plaintiffs wanted poorer student to pay more so they could pay less.

Smells like entitled wealthy people.