With regard to halal and kosher slaughter, I think the key issue is consistency and fairness, since that's what any society should aim for. Generally, I see all religious rights issues thus: There shouldn't be special privileges, but nor should there be targeted discrimination.

For example, if other elective face-coverings are banned somewhere for security reasons, I don't believe the niqab should be exempt. But if all other elective face-coverings *are* permitted somewhere, I wouldn't support a niqab-specific ban, much as I dislike what it represents.

When it comes to religious slaughter, I see that factoring into things in a couple of different ways. On the one hand, I don't believe a type of slaughter should be legal in religious slaughterhouses but banned in non-religious ones. Everyone should be under the same rules...

...regardless of any superstitions. So, that's a disparity, and it's fair for people to say, "If Muslims can do this, we should get to do it also."

On the other hand, if a society allows other forms of non-stun killing for meat, such as hunting, then that's another area of...

...inconsistency. In a society that allows meat farming, I don't think you can fairly argue for banning the shooting of game (assuming it's not an endangered species etc.) or fishing. In which case, unstunned killing's already a thing, and a halal / kosher ban seems more dubious.

Then you have to factor in all the other aspects of animal welfare. Factory farming of livestock's pretty horrific. Yet, as a society, we currently deem it acceptable. If you can legally torture an animal throughout its entire life, it seems inconsistent to then say unstunned...

...slaughter's a step too far. If the goal's a reduction in cruelty, we can't really have it both ways, and say other immense cruelties are fine, but this particular increase in suffering isn't. Similarly, countries that farm animals for fur probably don't have a great moral...

...basis on which to ban unstunned slaughter for meat.

Ideally, when it becomes widely and cheaply available, cloned meat will render slaughterhouses obsolete anyway. But until then, consistency in animal welfare seems like it should be the goal. And that has to work both ways.