Reasons why you might want to be in the arena:
1. Focused audience/ less comments to wade through
2. Less likely to have a vocal whine about your fight disrupting the magic flow of people entering and exiting.
3. Easier to log the fight when it is in a different room.
That is why I usually move it there BY CHOICE. Also if there was already a fight going on in the main room, it would make sense to do any other fights somewhere else.
But again i choose to do so. I think if someone chooses to do their fight in main, they should be allowed to keep it there unless something they are doing is breaking a site rule. Most people seem to never use the main chat anyway so they don't care. Heck i have known people who refuse to speak to anyone who actually says anything in main ! Yes how dare I use this chat room..

No one is forcing someone to watch the main room. Not everything I see here is stuff I even find remotely interesting but as a free human being I oddly can choose not to be forced to read it

. And if someone feels that militant that they need the main chat that is being used by the fight, why don't THEY move to the arena? Obviously they have some urgent thing that they must discuss with their group of friends in public so another room works just as well right?
Now if you are just bitching for the sake of it...your tough shit then

Also, if your reaction to a fight you don't like in the main room is to harass the fighters in an effort to force them to leave, you are the person acting inappropriately.