I totally get where you're coming from. I had similar conflicting thoughts watching the video. Humor's a tricky thing - when is a parody a critique, and when is a parody a loving send-up? I think that's probably why some people from Portland think Portlandia is hilarious and some can't stand it.
At the end of the day though, I think your analysis is a sophisticated one that stems from your deep understanding of the issues. I think most omnivores wouldn't "get it" the way you do, which is why I come down on the side of finding the video offensive - but to each her own! I appreciate you bringing a different perspective.