Just to be clear on something - I don't see a problem with "monster world". It's just not the baseline assumption. There are relatively safe areas, there are relatively dangerous areas. Halflings are probably going to be found in the former more than the latter.
In most cases though, I don't think most fantasy fiction really thinks through monster world nor do they accurately depict settlements realistically. Rohan in LOTR may have looked cool, but where were all the fields? What did people eat? All we see is this city in the middle of an otherwise empty plain. Did people eat air?
Video games are really, really bad at this. Because of limitations of travel and because they want something for the players to do, there are incredibly hostile monsters around every corner. Not only that, but the monsters increase in difficulty as the game goes along.
So it's fine if, like video game, you just don't care. I just disagree with adding a ludicrous number of monsters and then expect society to be similar to the real world or to assume that it's the baseline assumption for every campaign.
I've had pockets of my world (last time it was actually a pocket dimension) where being outside the walls at night was incredibly dangerous and literally everyone of every race had to retreat behind walls at night. If halflings had not been part of the group that went to the fortified city, they just would have set up their villages to be even more hidden. Homes built into the earth that they favor could probably be fairly easy to hide. Instead of open fields, disguise cropland to look like open meadows and so on.
But either halflings are not going to live in dangerous areas or they'll figure out a way to deal with it. Maybe they're a bit more militaristic than most halflings, maybe they're just good at finding out of the way nooks and crannies that nobody notices.
