Some institutions maintain separate SAP policies for institutional need-based aid vs. Title IV aid. Why?
Schools like Harvard, Yale, Princeton, Stanford, MIT, Northwestern, Dartmouth, Duke, Tufts, UPenn, Grinnell, Swarthmore, Wellesley, Dickinson, Macalester, Reed, Oberlin, Wesleyan University, Washington and Lee, Haverford, Bryn Mawr, Bucknell, and Middlebury maintain two distinct SAP frameworks: one governing Title IV eligibility (Pell Grants, Direct Subsidized/Unsubsidized Loans, etc.) and a separate one for institutional need-based grant aid. A student can fail federal SAP and lose their Title IV funds while still retaining their institutional grant as long as they meet the institution's own academic SAP standards.
I know state univ and colleges have to maintain same SAP policies complying federal and state aid.
What is the administrative and policy rationale driving this structure at these institutions?