Nirvana: This was discussed a while ago and i think Fencers answer was something along these lines.
If you are the Big Boss of a Fellowship, you only have people in there that you choose, and hopefully get on with, and that follow the rules you set down.
You have the power to remove anyone, who does not abide by your rules.

This i would normally agree with, but with one exception, when you have been left in charge of someones Fellowship for a reason of absence. Here it might be nice to have 'suspend a person' option where all there Fellowship privileges are halted (no read/write boards, joining Tournaments & Teams etc....).