Granted, the Cadillac comment was stupid.
But this was said in Michigan, after all. Emphasizing that you drive American-made vehicles is important. Stopping with the reference to pickups would have been fine.
Personally I won't own a foreign car. That was drilled into me growing up in Michigan — it just doesn't make sense to disrespect what was at one time the main industry of the state.
What other people do with their money is their choice. That's my choice.