We need more scary infinite variants of manmade environments like the Infinite IKEA or the Backrooms.
May I suggest, The Lot:
I’m sorry to disappoint you but this is a real parking lot. I didn’t edit it.
Check out the lot-to-building ratio in any large American sports stadium
Some lots are so big they have bus services specifially inside it. The lots are broken into sections and buses go around to their sections at a set amount of times before the start of something and drive people to the main building.
The societies of lost people inside The Lot would probably operate something like that to locate and pick up new arrivals and bring them over to one of the major settlements.
In the Infinite Ikea or Backrooms you can convince yourself there’s gonna be a door round the next corner or behind that wall.
But despite it being completely open, there is no hope of escape from The Lot. Whereever you look it’s just more cars from horizon to horizon.