When you have to take one of your own cats to the vet for the nth time to get it patched up after a fight with a feral or after you lose 85 baby chicks to a feral who killed them just for fun then killing the little vermin becomes pretty easy.
You left the chicks were they could get killed?
And that’s the cats fault?
I grew up on a farm raising chickens from chicks, with cats, pets and feral, and have NEVER experienced or heard of such comments as cats killing mass numbers of chicks for fun. Do you have any evidence of such cat behavior?