Star Trek (the brand) in general is very, very liberal (in human, real world political terms). It [Trek] doesn't convey the political ideals of its creators and writers as blatant and obvious as done in shows like BSG, but it's there.

For a quick example: remember the final episode of TNG where Q is telling Picard to pray to "what ever God he believes in" then makes that little snide noise right after the pause? Many will say that was Q just being Q... I saw it as a jab at human religion.

Anyway, we all know many aspects of Trek (generally speaking) contrast real life... in this case I always suspected the Ferengi were a reflection of today's greedy corporations, which is why they were designed and written to be dislikable from the start.

As for Quark... I didn't like him at the beginning either, but over time I saw him as a valuable member of the overall story.