@WilsonTurner Yeah, but I'm just basing this on what I see today. This takes place four thousand years in the future, farming techniques and waste recycling might be advanced to a level that I can scarcely imagine.
Think of a society in which all the nutrients are filtered from human waste to nurture the next generation of crops, which are produced in multi-tiered tanks which occupy a fraction of the space of conventional fields and do not need natural sunlight or any of the other limiters on our current fields? Well, they'd be able to make more than twice as much food. It may sound like fiction, but this is fiction.
Of course, there'd still be problems like you say, I'm just playing the devil's advocate to the normal issues of giant societies.