What is the EVOLUTIONARY ADVANTAGE...

of snoring?

It lets all the predators know where the fattest, most easily killable prey are, and so increases the net fitness of the population after these have been weeded out.

Similarly, it discourages the females from spending very long in the same bed, and therefore helps to prevent breeding by inferior specimens.

snoring means you have goo in your nose

http://en.wikipedia.org/wiki/Neutral_theory_of_molecular_evolution

There is little advantage in snoring. Humans have just been so succesful that minor inferiorities like this haven't had much effect on our evolution.