"To be a master of metaphor," Aristotle wrote in his Poetics, "is the greatest thing by far." Not, as we know from Plato, to be "used" as a form of rhetoric (which, as far as I know, he and the Socratic school disagreed with on an Ethical level with their Stoic contemporaties), but as a path to see the forms behind the shadows of his cave. Was, then Greek, and by extention, Roman Deification, as far as Frazer and Campbell declared it, seen by the post-Socratic philosophers, to be a higher form of truth than a literal interpretation of the narratives of Homer and and his predecessors? Is has been said that Socrates only read Homer. Is Campbell just reiterating Socratic thought on personification of abstract entities as being metaphors, or was Greek religion seen by these thinkers as the masses saw them: as actual Deities to be worshiped?
You can see :
Walter Burkert, Greek Religion : Archaic and Classical (German ed, 1977)
Daniel Ogden (editor), A Companion to Greek Religion (2010), Ch.25 : Greek Religion and Philosophy: The God of the Philosopher, by Fritz-Gregor Herrmann
Peter van Nuffelen, Rethinking the Gods : Philosophical Readings of Religion in the Post-Hellenistic Period (2012).