Not just for aid but because of the change that conversion brings:

Now a confirmed atheist, I’ve become convinced of the enormous contribution that Christian evangelism makes in Africa: sharply distinct from the work of secular NGOs, government projects and international aid efforts. These alone will not do. Education and training alone will not do. In Africa Christianity changes people’s hearts. It brings a spiritual transformation. The rebirth is real. The change is good.

[…]
I observe that tribal belief is no more peaceable than ours; and that it suppresses individuality. People think collectively; first in terms of the community, extended family and tribe. This rural-traditional mindset feeds into the “big man” and gangster politics of the African city: the exaggerated respect for a swaggering leader, and the (literal) inability to understand the whole idea of loyal opposition.
[…]
Christianity, post-Reformation and post-Luther, with its teaching of a direct, personal, two-way link between the individual and God, unmediated by the collective, and unsubordinate to any other human being, smashes straight through the philosphical/spiritual framework I’ve just described. It offers something to hold on to to those anxious to cast off a crushing tribal groupthink. That is why and how it liberates.

In this one article an atheist dispels two atheistic talking points: Christians are not freethinkers and Christianity is not a force for good. In the author’s experience not only is Christianity helpful, it’s essential if Africa is going to compete in the global market. They need to replace their current belief system with one that frees them and Christianity does that. It frees them from the superstitions that bind them and frees them to think for themselves. Take that, Hitchens! Refuted by the experience of a fellow atheist.