Woody Harrelson is no stranger to controversy, and he doesn’t shy away from it either. An outspoken environmental activist, Harrelson has attended environmental events around the world and is known to join protests that demonstrate alternative viewpoints.

He once traveled to the west coast in the U.S. on a bike and a domino caravan with a hemp oil-fueled biodiesel bus. Harrelson is also an ethical vegan and eats raw foods. Along with not eating meat or dairy, he also doesn’t eat sugar or flour. In Zombieland, in which he plays a character with an affinity for Twinkies, he did not eat the confectionery, replacing them with vegan faux-twinkles instead, made from cornmeal. He appeared on a postage stamp in 2011 as one of PETA’s 20 famous vegetarians, and he was named PETA’s Sexiest Vegetarian in 2012.

Here, Harrelson tells us how our spending has the power to influence harmful practices and help change policies at companies that are doing damage to our planet.