It's always flattering when somebody you really respect and like wants you to be involved in their project - let alone writes a part with your voice in mind.
We're told cars are wasteful. Wasteful of what? Oil did a lot of good sitting in the ground for millions of years. We're told cars should be replaced with mass transportation. But it's hard to reach the drive through window at McDonald's from a speeding train. And we're told cars cause pollution. A hundred years ago city streets were ankle deep in horse excrement. What kind of pollution do you want? Would you rather die of cancer at eighty or typhoid fever at nine?