Recently I've noticed a few custom flags (mostly coming from a particular room), where a user custom flags a message just to get the attention of a site-specific mod. (e.g "reopen this question plz", "explain why this was closed", etc)
Maybe the time has come to add on a "decline flag" option for these? Basically an option which will allow the mod to enter some text. When the flag is declined, the user will get a popup notification telling him about it (and a link to the faq page about chat flags).
Point is, custom flags are private. So I can't simply ping the guy in his room "Oy! That's not what flags are for!". I have to create a separate room for it, and that seems like a waste :/
As a side note: Are we allowed to chat ban users for misusing the flag system if they continue to do so after receiving warnings? (just a thought)