What does a believer think of when they describe their own beliefs about god? The most obvious answers are God represents love, at least in the Judeo-Christian belief system. Many believers think that without the loving benevolent father and the eternal hell fire alternative they would be eating babies, raping, and pillaging.
This is based on the assumption that God created humans basically in a state of immorality and without divine discouragement (threat of hell) humans would not sustain any form of culture and human society would fall apart.
But this is in fact not true, and in my view if we are in a truly moral society then someone is being altruistic they are doing it out of the goodness of their heart not because they are afraid of punishment. It could not even be considered altruism because it is meant to contribute to reaching a selfish cause (going to heaven not hell).
However this makes sense based on evolutionary predictions. We are selfish animals and we have a deep instinct to survive, therefore once affected by a meme such as a religious belief, like the good-bad afterlife complex we will do whatever we can to make it so we survive that afterlife in good condition.