I had not seen this commercial before. In my opinion, as an outsider, it's play on super-broad stereotypes of the rural South is exactly why it is both funny and not offensive. Sometimes, a representation of a stereotype can be so overwhelmingly over the top that there is no way anyone would take it seriously. I liken this to some of the absurdities of the Chapelle Show. His skits are so beyond reality and so exploitive of a stereotpye that the joke becomes the stereotype itself.
A woman in an elevator with a chicken chasing a pig named "Rocky Top"? Come on, that's hilarious and so over the top that no one would think to themselves that all people in Tennessee chase pigs named for their alma mater just because they saw it on that commercial. It is so ridiculous that it instantly disproves itself.
If you did one based on USC where there were a group of unschooled surfers speaking in some sort of west coast dumb slang (gnarly, etc.) you would not think that proof that people in southern California are all surf and beach bums. You'd recognize it as playing on a stereotype you know to be false ... and smile at how clever the commercial was.
And if they did one where they had some farmers husking some corn, you wouldn't think badly of Nebraska for it.
To me, the problem commercials are ones that perhaps a lot more subtly point out and take advantage of these stereotypes, particularly if based on race or ethnicity. But this commercial was so mocking of itself, really, that I just don't see it as anything other than poking good-natured fun at the stereotype, itself.
