In the apocalypse world, meat was not as difficult to get. Though it was hard to hunt animals that had mutated, it was not impossible. As long as the survivors could get past the psychological barrier, they would be able to eat the meat of the hunted mutated monsters. But the same could not be said for the plants that have mutated.
Unlike the mutated animals, the plants all over the planet had developed the same poisonous characteristics, which took years to suppress. Because of this, the price of vegetables was always higher than that of meat. Because of this, there was a sudden change in the dietary condition of the upper and the lower sections of society.