The group of guys I hunt with has been hunting together for several years. We divide our kills equally amongst the group and no one has ever shown too much concern for who actually pulls the trigger. We discuss it at the beginning of the hunt and decide who's turn it is. That said, we have an understanding that anyone who is by themselves and has a shot will take it. There is some good natured "discussion" about who gets to shoot but usually it boils down to who hasn't shot for awhile.
I am curious if most hunting groups look at it this way, or if there is more competition for making the kill. We view hunting as a harvest and are most interested in stopping the meat long enough to collect it and stick it in the freezer.