These are kind of mundane and are town-focused, but I thought they might add a little texture to the world:
Firehouse: Environmental protection gear, some tools, maybe an axe or two. Chance of picking up a truck. Maybe it could have a siren you could sound if you felt like spawning a huge pile of zombies?
Grocery store: Probably a good source of canned goods (and fresh food for a day or two). Kind of trivial, but it feels weird walking around this town with tons of gun shops and liquor stores but no grocers. I don’t know, maybe everyone does their food shopping at the mega store?
Barber shop: Really mundane, but it would add some texture. You could pick up a scissors, maybe a straight razor, some flammable hair spray. Or you could smash up the chairs for steel chunks.
Also, this is maybe a better encounter than an actual location but: Road under construction. Road is torn up, causing a navigation hazard. There are a bunch of dead bodies carrying tools and wearing hard hats. Maybe a construction vehicle (bulldozer, anyone?)