Situations like these are an inescapable consequence of population growth. As the number of humans increases, there will inevitably be less space allocated to i

Situations like these are an inescapable consequence of population growth. As the number of humans increases, there will inevitably be less space allocated to inefficient activity, where efficiency is determined by an activity's contribution toward sustaining the larger population. Herding 63 sheep is not as efficient as housing 5000 people or stockyarding 500 pigs. Growth is not 100% to blame, but growth is a sufficient cause for your story. It's worth tracking how well humanity copes with these inevitable changes.