I'm buggered if I'm wading through six pages right now (maybe later) but if I don't stick my oar in now it'll be another ten. Anyway, in regards to the OP, the Universe is simply far too big to be able to attach any one "why" to its existence. Hell, there isn't even a single country right here on Earth that you could do that to. We could reduce the focal length somewhat, even if the scale is still grossly out: for instance, why does a rose exist and what is its purpose? To look pretty? To smell nice? To get into her pants? We need to stop looking at these things from an anthropocentric perspective if we want even an atom of a chance of learning what's really going on, if anything. Science offers us a way to learn how things work and how they fit together with everything else, what happens to that everything else when one thing stops working, and so on.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'
