[otrs] Why agents can add clients?

Hi All, Before go to production with otrs we are testing it and some doubts are appearing. I don't want my agents are able to add clients, why they see the clients link icon on the menu bar? The only way i found to is removing "rw" permission, but i need this permission for the agents to see the queue. Maybe i am not understanding well the essence of otrs, but i am trying, testing. I hope you can help me again. Regards, Vince.