I usually have no concerns about someone stealing "my" kill. It only annoys me a bit when some of my Rook comrades dive for it, as we are usually in dire need of alt to face the habitual Lemming horde.
At the end, I could care less about who
the server decides which kill belongs to. The only important thing is that the enemy is dead and buried. And I know who deserve his scalp whatever the server says.
Being positive by nature, when I remove one wing from an enemy and a bunch of Rooks fire the falling remainders like there's no tomorrow, I tend to think I'm increasing my country gunning skills by providing easy targets to the ones so desperately needing.

No, I don't care anyone "stealing" my kills. In fact, If any rook wants, they can do it from me without hesitation. On my side there is absolutely no anger if a fellow Rook wants to blast the falling plane out of the sky.

Cheers,