Because we still want an answer, whether or not someone can give one to us.
Those kinds of questions might not have logical answers, but they illicit different emotional/theoretical/personal responses from different people. I think its human nature to want to share those feelings and thoughts with others, probably in order to help figure out our own thoughts.
It's almost as though you are asking why is there religion? Or why is there philosophy? I think the answer is just because we are extremely curious creatures, who's entire system of life and community is based off of the sharing of ideas, feelings, and ideologies.