My first thought was 'Food...'
I'm the go to gal in my family whenever a chicken needs putting down. So far it's been Opie, an alpha rooster who was terrorizing the kids and who also left some huge bruises on my back (but I assure you it wasn't revenge on my part I adore animals really).
You'd never see this in China or Vietnam or Laos or well you get the idea. Places where chickens are viewed as food and not pet stock :)