If it bothers you that much, don't go in there. We gotta eat sometime and most of the time it is not cruel to eat animals or we kill our own animals in the most humane manner as possible.
You would be singing a different tune if those predators, like the possums, coons, foxes and dogs killed your chickens and they will keep coming back until you have no more. I was like you when I was younger but after suffering heavy losses, my thoughts changed and I do not feel any remorse in my actions in killing them. I protect what is mine unless it is a protected species. A .22 in the head or heart is not cruel. Its quick and painless. I won't relocate them either. If they had babies, it is case by case decisions.
Oh yeah if you think too much on the effects prior to death, they fight back to protect themselves while we fight back to protect what's ours. After you lose alot of your birds, then you can tell me what your thoughts are and what you are going to do about it.