As any user can create a Chat room, there is a possibility to add a user wrongly.
For an example, a user from a particular team can add a user of another team with his Chat Room wrongly. At that situation, the other team user should easily exit from the wrong Chat Room and don’t depend on the user who created that Chat Room. Hence, we didn’t add restriction to exit from the Chat Room.
Anyhow, we will consider the Chat Room Lock option and implement at Server Manager in future.
Thanks for your suggestion.