Well we should all just go our merry private lives, since after all God has no "need" of us. Let the gospel preach itself!
That's an extreme which Calvinism has sometimes gone to and it's silly. You can count on that if God created you, God wanted you to be there. Let the light shine from lamps of a billion different designs.
rwfromkansas is right.
God does not need us. To believe otherwise indicates a fundamental lack of understanding of Who He Is.