Is this about animal welfare? Or some other thing?
Let's assume it's about the first then you may care to consider the harm humans may inflict on their animal cousins.
We kill animals for sport. It's called hunting. As in the grouse thing.
We kill animals for food.
If you realised that both farming and hunting hurt animals and that was your
sole concern you would be equally opposed to both, wouldn't you?
But if you acknowledge a reliance on meat as a food source, then, and reluctantly, you say, OK, we need the abbattoir, but we don't need men on horses chasing foxes.
So that's a rational for allowing industrial scale torture, while banning its local artisan forms like fox-hunting and hare-coursing.
But a necessary stance of those believers in animal welfare, but who've accepted for pragmatic reasons a morally compromised position, surely, is that having had to accept a necessary evil we can, at least, mitigate its worst effects. Which is why we have laws governing the transport of animals for slaughter and the methods by which they're killed.
How many people who've signed Melv's petition would sign a similar one banning halal slaughter? Or even care?
https://www.independent.co.uk/news/uk/home-news/lancashire-school-halal-meat-ban-muslim-leaders-court-halt-review-animal-welfare-rights-unstunned-a8124551.html