a warrior needed on a willpower piece only because he was a new player and didn't know any better until we politely explained roll etiquette to him.
This. I was doing a Heroic on Coruscant and a Sentinel Needed on a Cunning Implant. When I asked why, the answer was "I don't have anything in my Implant slots yet, so I need it, don't I?". It was a F2Per and obviously not very experienced one, so I explained and we moved on. Sometimes people are really just unaware, and thus there should be a place for the benefit of the doubt - especially on low level planets.