Veganism is the belief system "to exclude, as far as is possible and practicable, all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose."

In that essence, the are vegetarian right off the bat. Any food that contains animal product is a no-no. But It's not that clear on sugar based junk food though. Say for example, Nestle products are rife with Child labor in it's product manufacturing process even if the product does not contain animals. 

Does chocolate made from child slave labor still considered vegan?

reference: https://www.confectionerynews.com/Article/2017/06/12/Nestle-top-in-child-labor-report