I am in MA. It is completely, totally, and 100% legal for an employer to require an exempt employee to use vacation, sick, personal, PTO, or any other form of paid leave for partial day absences. They may also require an exempt employee to make up time missed. (P.S. the only state in which this is not true is CA, and even in CA it is true in some circumstances).
Being exempt means you are exempt from overtime laws. It does not mean that you can come and go as you please or that you are exempt from other company policies.
PAY cannot be docked for exempt employees except in very limited circumstances. PAID LEAVE can be docked in both full and partial day absences. There's a difference.

