I think that it was fair game as political commentary but a piss poor joke.

Folks here have made some good points about Volkswagon's role in the hippie movement. May I also point out that translated the name could be interpreted as "folk's car".

History of Volkswagon

Apparently the name "Volkswagon" was Hitler's idea and it is among his strongest and most lasting legacies. Geoff Berner made a valid point. I fail to see the humour.