Veganism does not necessarily entail anything beyond abstaining from any and all animal products and/or by products in one's diet. The obvious is meat but extends to eggs, milk, cheese, honey, gelatin, etc. A vegan could wear a leather jacket, though. They are not eating it, after all. The associated philosophy of veganism includes the diet and also extends beyond it to oppose the use of animals for any purpose. Even meat eaters are opposed to cruelty to animals. Businesses that operate using ethical and humane means of growing and killing their livestock thrive because meat-eating people do care about such things. Maybe not all, but enough to sustain enterprises that offer such products.