This is for two main reasons:
so - Adam can be longer the at the top of the online users box
1) So new users are familiar with the authority system. Let's be real here, a lot of users register only for chat so this would benefit them.
2) It would make chat look a bit more, aesthetic? Currently all we have is the chat, and a box saying who is online. I also think it help who is expert, editor etc.
Hope this suggestion suffices and thanks for reading like 3 paragraphs.