The admin chat is used "appropriately", at least from what I've seen.
In cases where it's strictly related to staff duties, common examples are:
- Yo [staff name here] have you handled the report on
- What do you guys thinks about [random bloke]'s 12 recent warnings? should he be banned?
Both of these I have witnessed in game, and other times its simply just casual friendly chatter between staff.
Cases where someone spams the staff chat with incoherent gibberish is a different ball game, but I am yet to see this kind of issue.