Humans fist fight all of the time and, unfortunately, hit each other all of the time. Hitting stuff isn’t exactly rocket science.
Also, yes, at the initial phase many would fall victim to hordes of zombies and their bites, but zombies remain unarmed and stupid. People have lots of protective gear at home. Leather jackets, thick pants. There’s no way someone simply bites through my boots and my riding coat, bit yes, I’d need a helmet. Quite a few helmets around, though, and lots of helmets to be looted from stores. Bolas are easy to build, Stakes too, Humans can climb, Zombies can’t.
If it’s an extinction level event, it’s because of the failing infrastructure, not because of the zombies themselves.
