Initially it would be a group of people who get together for RP's.
If it has S:ARG in the title, you're supposed to be able to tell that it'll be an RP full of dedicated players.

RP's either created by the seniors or by any member should be treated the same and held in the same regard. The want is to have RP's which'll last and not have so many dropouts. 

If the RP is hosted under S:ARG title it would be for S:ARG members only which hopefully would give it good quality since membership is earned.
Back in old-guild era we were often called Elitists because of our high standards and "exclusiveness".