People are afraid of death. Thinking that they won't really die makes them happy - feel better about themselves. Humans are aware of their own impending death, but are in a high level of denial. It's probably because society today is so selfish that they cannot picture leaving everything that they've accomplished here - and have nothing afterwards. A heaven - could be a place of pure happiness, and have powers that could provide anyone with whatever they desire.

This, motivates them to "work hard" to reach heaven. Stupidity at its best.