I thought so at first, but there are two reasons that make your statement invalid.
If they use chat and speak using @, it will say (ADMIN).
If you open tab, you can see the <ibis.a> tag.
The reason they created the group was to create more room in their names, for whatever reason. However, I do like the idea that it is invite only, as it creates a way for those who know about it to contact other admins in the event that they need assistance.