Read the link you posted to the Mac website. It clearly says that Mac’s EA is non-restrictive. From the page:
————
EARLY ACTION
Early Action is a non-restrictive option for students that are ready to apply to Macalester on November 1. Early Action applicants receive their decision by December 19. Those who apply for need-based financial aid can expect to receive their financial aid result in mid-January.
—————-
Also, as a parent of a child who applied ED to one school and EA to Mac, the process was that Mac asked applicants to update their withdraw status if they were accepted to their ED choice. There was no mention in all of our communication with Macalester that applying ED elsewhere was a problem.