As an animal I would understand the purpose, it's all about survival.
As a human I have no idea, we are probably at the worst period of human history. Religion colapses with modern standards, overpopulation, we can't find a proper transition from fossil energy to clean energy whether because of lobbyist or technological limits, overproduction (overfishing, meat industry).
That last one disgust me at the most, we kill more animals than necessary to fill the supermarket of products, the rest is left in the trash can when its outdated. This regards mainly developed countries.
I don't eat meat since maybe 10 years now, because of this very reason, I would like to stop eating fish also. But then all I have to do is ctb.
Nope can't find a good reason too.