Mine don't.

Unlike cats who are obligate carnivores, dogs are "opportunistic carnivores". They are able to digest plants, and a high quality vegetarian dog food is actually significantly healthier for them than the " grain-free" diets that have become so popular in the last few years and have been linked to increased heart disease.

"Utilize" implies that animals are a resource for consumption instead of living things with their own right to live. As another comment pointed out we don't "utilize" humans after they have been murdered. A goal of veganism is to stop factory farming but it is not what veganism is. If you consider all animals as having a right to life you then wouldn't consider their bodies as resources after they were murdered but instead as victims.

There are social and intrapersonal reasons to avoid eating meat even if doing so doesn't lead directly to more animals being slaughtered. It is still treating the dead bodies of animals as a commodity, something we don't do to the bodies of dead humans. And it will take a cultural shift in how we see animals in order to end their oppression.

And the issue of eating "wasted" (weird way to talk about it as a vegan) meat is more concrete when you are eating meat at a function or the leftovers of a friend. The next function is going to have just as much meat if not more because it all got eaten. Your friend isn't going to think about reducing their meat consumption because they were left with too much, they might even get more satisfaction from you eating it because of pity. People who regularly consume animal products often think going without them must be suffering.

I don't agree with freegans, though I also don't really care what they do. As long as they understand there is a clear distinction between something like dumpster diving and a potluck.

By definition, Vegans would not. People who would typically define themselves as "Freegan".