I agree with the underlying message of this episode, absolutely, and I probably wouldn't have put my thoughts together to realise it myself.
That said, the pigs-and-slop analogy came across as unbearably superior; just a step above unironically calling the cinema-goers "proles" or "hoi polloi". I realise it wasn't the intention of Bob to patronise, and that the fact of the matter stands, but it really was a crass choice of analogy.