Manage User Group Subscriptions

Unless I'm missing something - I've found it very difficult to manage the groups that users are subscribed to.  I know that users have the ability to join/leave groups once they've logged in, but we're using this application in such a way that we really don't expect the newsletter recipients to ever login.  I find it frustrating that I cannot manage a particular user's group subscriptions once they've been added/imported.  If there is any way around this I would much appreciate the guidance.  Also, consider this a feature request for the next release.  BTW - we are running on SQL Express.  Thanks.