Herm...Saruman was killed over the control of the Shire, Halleth was slain over the control of Rohan, and Castamir (I think) was slain over the control of Gondor.
So, the house of stewards was the only place where someone wasn't slain over the control of said place.
Oh, that's good to know. But I'm still keeping my holy hand-grenade close, just in case.