Which, interestingly, is exactly the reverse of what the relationships between Paladins/Clerics and deities was in 3E (at least in my campaign world). Paladins were the champions of 'good', i.e. more of an abstract principle, while clerics chose to dedicate themselves to a certain temple (and thus the worship of one or several related deities).I think Paladins are more focused on advocating and avenging a specific god, whereas Clerics are broader in divine concept.
But I agree with the notion that character classes in 4E are not really meant to represent a certain group or cultural role in societies. For me they're just building blocks to realize a certain character concept. Their background is entirely up to the player.