You don’t think starving zombies know how to walk?
Once they got the idea that things weren’t going to come back they’d be on the hoof.
Millions of them. And not just the gang bangers. The socialites, marketing managers, school teachers, doctors, nurses, and the engineers needed to fix what got broken.
Once the cities burn to the ground the odds of fixing the infrastructure in less than a year get increasingly dicey. Especially if major roads are disrupted or destroyed.
You act like it is one person against the mobs. There is a whole section of society that while not being “true preppers” are able to survive and band together to combat the hoards and we are well armed and stocked. Not just with ammo and food stuffs, but clothes, tools, books that tell how to build/repair things (not on a stupid Kindle either).
The mobs will get thinned out quickly in the Texas sun walking anywhere more than a couple miles. If things really go that bad then I venture that some would go on the offensive and try to engage interlopers away from the homestead.