Some schools/states require the FAFSA to be filed for merit only because they want the applicant to prove they are an eligible citizen/status. It is a way to require SSN and status without the school having to do the background check. They don’t really care what the EFC is.
Years ago Florida required the FAFSA for the Bright Futures award but no longer does so (and no longer requires citizenship/legal status). I think a lot of the federal government scholarships require FAFSA just to establish status.