step outside of your city mind
Open up Google earth and look at all of the land too steep or rocky for farming practices and consider that this is where the cows are raised. Very few of the global cow, goat, sheep herd are fed stuff from the farmable land. They also eat a large amount of the byproduct of human food production, such as orange peels and almond husks, asparagus stalks (the 2/3rds of the stalk that you don't see). Plus the fact that the food supply is a web and not a chain. There are many grains used to feed livestock and people. When the grains fall short the livestock become too expensive to feed. The livestock are slaughtered and become part of the food chain easing up the supply and feeding the people thus further easing up the food supply. The global exchange of food and commodities keeps us all fed. The real danger is the possibility that some pointyhead politicians will put their grubby mits into the works and mess it up (ala Mao Zedong and Stalin) that is how starvation happens on earth. All of our recent incidences of starvation have political causes.