It would be useful if, when a group admin sends a message to his/her group members, there is a tag on the message saying something like:
TheMoney, admin of XYZ Group
[You have been sent this message because you are a member of XYZ group.]
Also, might do well with an opt-out unsubscribe from the group link. Clearly the group admin title is not necessary unless the user is sending that message through the group messaging system.