Replying to Repair kit contents?

I've been reading several articles about what an AT repair kit should look like, so I have a pouch and I'm stocking it. I see a small tuft of steel wool mentioned in many lists (in case a binding screw strips) but see no mention of carrying replacement screws. I guess I envision that if a screw or screws are coming loose, you may lose 1 so carrying a replacement screw for your bindings/skis may be wise.

Would this be a smart item to carry, or am I worrying too much?

Thanks!