Very Low Zombie Count B42

When I first started playing B42 I thought the population count was insanely high. It seems a recent update flipped it to the complete opposite. I just looted the entire unnamed town with the military surplus store and killed 4 zombies the whole time. I came down to Muldraugh expecting a battle but I am strolling along the main highway looting stores at will, killing less than a dozen zombies along the way.

I thought maybe it was due to me fuckin up one of the settings, or my save file not handling a recent update, so I restarted on a straight "apocalypse" playthrough, but it seems that towns are still ghost towns.

Is this extremely low pop count by design?

My operating theory right now is that my computer can't handle the game and has to de-spawn large amounts of zombies, or fails to render them. With one of the recent updates (the same one I suspect of killing the zombie count), the framerate has been terrible. Driving over 60 miles an hour gives me tons of lag, and driving in the rain is next to impossible.