Another of the many reasons to hate vegans.
This isn't a vegan issue nearly as much as it's a control war waged by leftists. While I think it's bizarre to want to name the animal before you have it slaughtered, it isn't quite so strange when years before, children would name an animal on the farm, feed it and care for it, before the same fate befell the animal.
The process gave kids the understanding that animals are ultimately food (for some species, at least) and while there might be some emotional attachment, in the end, the food part wins out.
Violence at the hands of these hand-wringing zealots thinly disguised as vegans is but an indicator of a much larger and uglier quality - leftists who want to control others.
There is no other explanation.