EdenOne, you bring up an interesting, although false, dichotomy. The basic problem with your scenario is that it is very one-sided. You only tell the good, positive side of the story--the humanitarian believer--while ignoring the fact that there have also been many atrocities committed by religious zealots who acted according to their beliefs, often the very same set of beliefs as your good Samaritan.
In contrast, there have likewise been a great many good deeds done by nonbelievers, secular humanists (with or without that particular self-identification) that are simply altruistic by nature. That behavior can just as easily be explained through the lens of evolutionary biology.
This is why it is so essential to separate what a person does from what they believe. They are not--and I've attempted to make this point repeatedly on this thread--intrinsically linked.
In the words of Steven Weinberg, “With or without religion, you would have good people doing good things
and evil people doing evil things. But for good people to do evil
things, that takes religion.