[Happy Monkey]

The "haves vs have-nots" view of the world is a completely different axis to the religious/nonreligious view. If you don't want to help less fortunate people, and you're religious, you just say that the way things are is the will of God. If you don't want to help less fortunate people, and you're not religious, you just make that social darwinism argument (Or, in either case, you can just admit you're selfish and/or lazy). If you're generous, you can either say that you are carrying out the will of God, or that you have empathy.

The view that the only reason to help the less fortunate is because God says so is a very simplistic ethical system. Your characterization of nonreligious people wanting to let the weak die to increase the strength of the species is one of the confusions you are succeptible to when you equate evolution with religion. Evolution is something that happens, not something to worship.