When I'm mowing the lawn I always aim for the small animals.
What make you think running over animals is smart thing to do?
Who cares. I just like to kill small animals.
Animals are not here for your amusement and running them over with your mower is cruel and sadistic. Find a different way to get your jollies.
It's just a few mini cows and sheep. Besides, I won't miss killing them. It's not like they are pooping all over my lawn. It's not like I'm killing any more people.
You could find it innocent to kill small animals, but they're still living things and you should never take a life. When you're willing to take a small animal's life then it means you could slowly build up to being able to kill a larger animal until you're in a bad place mentally.