I'm boycotting the car industry and big oil by not having a car in the first place.
Yes I know. You couldn't do it and you need a car. Your car is so very practical. You think I should also have a car because they're so useful. I know my food is hauled by trucks burning oil and that I contribute unwillingly anyway. But I arranged my life around the fact that I don't need one, and I'm glad to avoid contributing to this horrible industry.
Fuck cars.