More and more lately I notice people (mainly the 40 and 41's) join a run such as Infested or UCS and immediately they go into "busy" mode and then they leave. It happens over and over again. It doesnt seem to matter if every other player in the instance is a 40+, or if the run is going smooth as pie. In my opinion they are wasting a space that a player who would actually play and participate could use. What are they doing?