Overkill

I happen to live in a housing complex surrounded by rice fields. I enjoy the green and fresh atmosphere. As the paddy get yellowish near the harvesting time, the farmers are busy fending off small birds. They used noise making instruments to scare or startle these starving birds, including not so inspiring scarecrow, made from crisscrossed woods donned with shabby used clothing. They seem to do anything possible to save their soon to be harvested crops. However, one thing that I noticed, they never try to harm these birds. They only scare them away. I was wondering if there was some kind of philosophy about it.
Anyway, as I was riding peacefully to work this morning, there was this one guy with a long sniper-style air rifle, he seemed to be aiming at one of this little birds. I didn’t see whether he succeeded or not but that very sight got me thinking (yay…) all the way to the office. Why would he want to kill such a small bird, he can’t really eat the bird (technically yes, but you need lots of them to make you full). Is he practicing on his shooting skill? Well, pick on someone (something) on your own size dude..