Since purchasing and consuming animal products both depends on and contributes to animal agriculture, and animal farming necessitates rights violations against nonhuman animals, not being vegan when you have the option is synonymous with support for injustice. I believe that as leftists who purport ourselves to strive towards a more just society, and as human beings who generally value nonviolence and compassion, we should hold ourselves to a standard that doesn’t allow for the perpetuation of mass-slaughter. Let’s discourse!
They do try and reintroduce predators like wolves into Great Britain, but there are 2 million deer in the UK and it’s not really viable to introduce enough wolves to combat that amount of deer in any kind of short time frame. As well as this, some of the most common deer species in the UK are non native so they shouldn’t be there anyway.
And your second argument is true but rather extreme since we should in general value human life over the life of other animals.