Unless there is some clever kin selection pathway, there is no way for evolution to know of this benefit, as the genes that implement the suicide die with the host and can't be selected for. If there is such a pressure to get rid of inefficient members to make room for the others, it's easier to suppose that other members will get rid of the inefficient ones (or simply the ones unable to defend themselves).
6Cyan
Why would evolution react to the concerns of society? This line of argument seems like group selectionism to me.