Not all communications sent to internal audiences (osu.edu/osumc.edu email addresses) are transactional in nature. Each committee or special group may need to send to their members or invite to events. At Ohio State, transactional internal communications are messages sent to faculty, staff and current students as a condition of their employment or enrollment.
Emails that are voluntary in nature (i.e., not transactional, not required due to employment/enrollment) require a subscription and a method to opt out, regardless of the intended audience.