Dogs are not free from human slavery, FAR from it. Non-vegans will look at a dog and think about how the animal will benefit the human - be it for sports, entertainment, testing, work, or consumption - all because they still hold the false belief that animals are here to serve human beings. As vegans, we reject that idea completely. When we look at an animal, we see them as an individual, NOT as a commodity.
Veganism is the PRINCIPLE that humanity should live without EXPLOITING animals.