We also kill other animals out of necessity, for the same reason lions do
Lions are obligate carnivores, they have to eat animals or they die. We don't have to eat animals, that is a choice. Necessity suggests that we have to it eat it.
When you sit down at a restaurant and have the choice of a beef burger or a vegan burger, there is no necessity that you eat the beef burger.
Veganism is a fad diet for privileged Westerners who don't either don't realise or refuse to admit that the omnivorous agricultural industry they hate so much is actually responsible for the food security that allows them to indulge their virtue signalling.
Veganism isn't a diet, it's a moral belief that an animals life is more important than taste pleasure. That doesn't even touch on how terrible animal agriculture is for the planet, it's not sustainable at all. I don't understand the prejudice towards vegans who at the core are simply being kind towards all living beings.