Likely a moot point as I am unaware of any boarding school which allows boarders to have cars. Of course there are schools on the border, e.g. PEA, where it’s possible there are day students with a Massachusetts license.
There are several schools that list the possibility of students in good standing having cars in their FAQs sections. We asked these questions of schools as well when exploring options of getting to club sport activities away from campus. Some schools very well have options for students to have cars.
The likelihood that a school in a more densely populated location would not have the space for students to actually park is a different story.