This is natural phenomenon in Japan, called "Kagiroi"
By the dictionary, the meaning of sessho is "The taking of life". But I listened to very interesting lecture from Zen priest on last Sunday.
The meaning of "sessho" is not only taking the life of living creature, he said.
Roshi(Old master) said that the meaning of sessho is waste of living creature and inanimate object.
For example, hunting for fun is absolutely sessho. But the hunting in ancient is not. Because, ancient people used all of game body. They ate all meat, they re-used skin, they used bone for some kind of tools. To use all without waste is not sessho. Same as object things. Making full use of object things is not sessho. But, disposable and easily abandon thing are sessho.
Therefore, whatever living creature and inanimate object, to make full use of their life which is the reason of existence in the world is not sessho. So by that reason, killing and not killing are not problem. It is a proposition that it is important only whether the life can accomplish the mission.
It is impossible for one life not to threaten other lives and to complete it to begin with. I think that it is difficult to complete longevity without sacrificing other lives even if it is the comparison bacteria and a plant. That the life that became extinct glistens in the life that let you become extinct in Zen is the problem. Therefore, Zen sect defends a simple saving. And all things are valued until being used completely.
Instead of completely using up every life without waste in Zen, attention is paid to the one of the small dusts. It is just same as ecology philosophy. The animal killed to eat is held of a service in the Shinto shrine and the temple in Japan because the deep gratitude is put. Even the life article and toy which were not usable also. I think it should be very unique custom.
In Japanese language, we say "(頂きます)Itadakimasu" before meal, and "(ごちそうさまでした)Gochisousamadesita" after meal. We Japanese always give thanks to killed animals, plants and people who involved by these greeting. I don't know similar word in English and some other languages.
Thank for minding food and things. If we do so, these foods and things can accomplish the mission in this world. I believe we can do it.