An example might help: Elon Musk is not, AFAIK, vegan. But he's done a lot to popularize electric cars, having far more impact than he could by changing his diet. Likewise, the Beyond meat people have probably done a lot more to reduce meat consumption than they could ever outweigh by eating steak every meal for the rest of their lives. (I am actually not clear on the net environmental benefit of using gas vs. making more batteries, but let's say for the sake of argument that electric cars are an environmental benefit, since it's just an example.)