Comment 2 for bug 1521767

Sounds like a good idea to me, to make this behavior consistent. Group admins can still turn it off if they want, and users can unsubscribe themselves.

Alongside this it would also be good to have better subscriptions management and an opt-in/out step when a user is being signed up for groups. See https://bugs.launchpad.net/mahara/+bug/1256722

But, that's another issue. :)