The belief that the universe was empty, then it wasn't, then splat you have a god who then goes on to create the entire Universe.
God is the eternal self-existing one, there was never a time when God was not present.
People are naturally charitable. It's in our DNA, since we are a social species that tends to live in packs. Wolves are charitable to members of their pack as well. So, with non-profits, some people start them because they are charitable, and some people start them because they are charitable, and use Christianity as an excuse for why they feel that way.
Interesting, do you have source for charitable DNA? And what do you see as the primary advantage of charity, doesn't that conflict with Social Darwinianism?
Further, Christians are more likely to be charitable, as charitable-ness is a command in Christianity, I reject that people are simply using Christianity as an excuse to be charitable.
Athiests might be charitable, if they want to loose the extra money, or time, but experience speaks that unless you have an over abundance of either you are unlikely to be charitable. Humans are inherently greedy (which I doubt you would dis-agree with, even from a purely atheistic world-view).