Jingo2, I would have to say because people are people and they make mistakes. Funny thing about people they are not perfect (Well maybe you are) I have turned on to fill the tank, noticed that the hat wire was down and went to fix it, ran into some snags came back an hour later to see that tank was more than full. I had every intention of turning it off but Sh!& happens. (I now have a timer I turn on when filling the tank, I tend to get side tracked allot.) …Oh … Squirrel ……………… I’m sure it was not her intent to leave the door open but it happened, the question was why do wild animals kill more than they need. An example: we had a small bass in a 50 gallon fish tank, we would feed him once a week with a dozen medium gold fish, he would eat as many as he could, there were lumps in his body, then he would either kill the rest or just keep them in a corner. He could not be hungry there were tails coming out of his mouth, it like once they start they just keep going until their done. (Feeding frenzy, Killing frenzy)
I've trapped predators for nearly 40 years, and I still can't figure out alot of the whys, but with coons in the henhouse I think they get in a frenzy from all the clucking, flying and fleeing and lack the reasoning to know they've killed enough chickens for a meal. No proof, jmho.