I think the more interesting question is why an entity possesing the ability to create an entire universe from nothing would not also implement a set of physical laws that allow life to evolve automatically? Why would said entity go in after the initial creation event and manually tinker with biological molecules to get them to develop into complex life forms? Sounds like a huge kludge to me. I prefer to believe that any supreme being that may exist is competant enough to get the laws of physics right the first time. Tinkering and hardcoding workarounds for the mistakes is not eligant.