Multiplying competing factions by reducing herd size leads to competing standards of what is acceptable when it comes to obtaining limited resources.
https://omny.fm/shows/clear-vivid-with-alan-alda/robin-dunbar-circles-of-friendship
If you were to divide people into groups of 150 people, in a city of 8 million people, each group with its own set of standards, total chaos would ensue.
This is the point raised, though not explicitly stated, in the shoplifter story below.