Amusing, maybe. Might need to be the subject of its own mapgen addition. o3o
Could add more production based NPCs too. A farm that has a farmer on it. Dunno how hard it be but would require some coding would be to say NPCs based on who they are will value what they need more.
Farmer would highly value new types of seeds, but have almost no value for crops and seeds he produces.
But he would absolutely love a bag of commercial fertilizer.
Hmm, not sure, that might entail a lot more scripting. XP
Yeah, I kinda figured. I just make suggestions and then let the developers/modders decide if they are worth adding. 
A farmer 5 days after Zday would likely have a gun or 6.
Im trying to imagine the kind of person who would reasonably try to wait it out at a farm and farm up. And how they would react to new people, groups, and attmepts to trade, sneak around, or loot him.
What skills does he have? Would he accept an offer at farmhanding? would he train you? would he feed you? would he let you stay a night?
How would he defend himself? Would he be ther because he likes to farm, wants to stay at his/this home, or is pretecting something, like his fams?
I do like the idea of expanding with more hints of post-apoc society, yeah.
Still, I’m trying to think of the best first steps towards adding more basic NPCs in static mode. Hmm. Easiest would be things where you don’t NEED NPC groups. Like a hunter, possibly with a fixed quest (jabberwock maybe) in cabins, or police NPCs in police stations (or maybe even jails), etc. Stuff that can be easily added in with the least source tweaking, as a start. o3o