They aren't. I think it's because we usually eat more plants than we do meat? So they're good for cutting and chewing up tough things.

[ He's pretty sure someone told him that or he read it somewhere. ]

And forks and knives [ he gestures with each as he says the word, for Mumble's benefit ] are useful because sometimes things are too big to break down with our teeth, or would make a big mess and waste food if we tried. Here, though, this should be easier.

[ He holds the tray with the bite sized pieces of now de-boned fish out to Mumble again, pretty sure that he's just going to go for it face first again and resigned to that fact. ]