How do you know they aren't RPing over microphones ? Or in their heads ? Anyways the more the merier and indeed see how it goes. People don't have to RP openly in orange/brown writing or using say you know?
People named "HipHop" or "SleepyBurger" are not roleplayers.
Plain and simple.
And a roleplaying server is actually about roleplaying with eachother, not roleplaying with yourself in your head. You can do that on any server.