I agree that main owners should be hidden from everyone else in the chatroom, for all the reasons both @Solange and @Cupim mentioned. Chat staff seem to act different in the presence of their main owners, and there really isn't any alternatives for sitting incognito.
In terms of chat staff, at ARCbots for example the owners I make are really the face of my support team. Any problems moderators might have gets routed directly to the owners. One of the most useful tools is being able sit and watch the entire chat without being seen. I'm able to see how situations are handled and how