I thought they said their ads were targeted? I'm not sure about the quality of their targeting... However you got off lightly, Chris; facebook seems to think I'm gay, live in San Fran and lead a somewhat "alternative" lifestyle in the evenings :-S Go figure.
However, it does really annoy me why people keep up the false belief that bio diesel is any good for the environment. Putting the prefix "bio" in front of something doesn't make it good: "biohazard" and "bio-warfare" are good examples.