Killing animals is a ruthless act, then why do Muslims have customs to sacrifice animals?

Animal meats have been part of human food chain as a source of protein since early ages. Even now our foods come from animal sources. The slaughtering of animals is a symbolic gesture whereby a Muslim declares his readiness to lay down his own life and everything he owns for the sake of God Almighty. The animal that is sacrificed  represents the animal in man himself. The Holy Qur’an states,

“Neither the flesh nor the blood of your sacrifices reaches God, but it is the righteous motive underlying them that reaches Him.” (Ch. 22:38)

It is worth noting that the animals slaughtered for sacrifices are meant for use by humans and in that category the meat is distributed to poor people, family and friends.