The goal of chats is to take one more step in the direction of eliminating email submissions, because most of us hate email submissions (note that you have an option to disable chat in your station/show's settings). It also means you never have to leave SubmitHub when coordinating / signing off / sharing a song.
After a while, you might find your chat list getting out of control. Pro tip: if you visit your Approved tab (or shared), there's a button to message the user associated with that submission. It's often way easier than trying to remember which name was associated with which campaign.