oh, mine don't have the hook in front, they're more like schooling tights I guess. So I can't really help you there. It could be that you just got a botched pair with the stitching not as tight. I can't tell exactly what you mean by the latch "pulling", do you mean it's like pulling against itself? There is always the possibility that they run small, like Ariats do (I can wear my normal size in their tights, but not in their breeches - unless I decide breathing isn't important lol).
also, this is completely off topic, but your cat looks really soft haha