Beware of deconstructing traditions, because you may miss reasons why that tradition benefited the society that maintained it. Keeping traditions is conservativism. The Jewish tradition behind kosher slaughter isn't really a ritual like halal slaughter is. It's essentially based on a fear of consuming blood. The modern interpretation of it is a bit strange; ancient Israel didn't turn cows upside down so they'd bleed out easier. I don't think they did it for smaller animals either. Might've done it for poultry. I haven't seen anything about practical reasons why you'd want to avoid consuming blood. (Unless you want to flush out the vampires in your community...) Might've made meat less likely to spoil perhaps. It could have been the personal preference of the rabbis in some early Jewish community. It might've had health benefits to not consume blood in the past; there might still be reasons to avoid it. I don't know. The "stunning" method seems to be more humane than slitting an animal's throat, within limits, at least using modern methods. (The old stunning method, where you basically hit the animal with a sledgehammer, was more problematic.) I've heard of issues where the procedure wasn't performed competently, where the air gun wasn't applied properly and left the animal in serious pain. Those appear to be edge cases. I don't know if the end result is meat with more blood left in it, when the air gun kills the animal outright instead of letting it bleed out, or if Jews are just being pedantic about it. Halal slaughter is similar to kosher slaughter in that the animal's throat is cut and that Muslims are prohibited from consuming blood. The main difference is it requires someone to pray over the animal as it's slaughtered, which makes the "ritual" label more legitimate.