The development within the base was initially planned, but no one had anticipated that God's opened window would destroy everything.
Humans evolving into a new species indeed endowed mankind with the ability to fight against zombies during the early stages, but it caused a drastic reshuffling within human society!
No one expected that survivor bases intended to develop according to plan during the apocalypse would turn into a survival of the fittest scenario after the emergence of the 'new humans', with ordinary people reduced to the status of livestock!
In the apocalypse, everyone scrambles for resources. When a shop appears selling water and food, who has the right to sell these goods?
If you are an ordinary person, even if you have a good heart, you would throw away all your morals and resort to stealing or robbery. It's human nature. No one can stand to see others living a carefree life while they themselves suffer, especially when they're only separated by a thin wall!