Oh please don't get me started in the original Colonization, that is my favorite video game of all time! I had so many automated wagons moving across the map, picking up goods (and food!) and taking it somewhere else. It was fun to dump food into the University colony to keep gaining fresh Free Colonists and then training them to be Elder Statesmen or Veteran Soldiers (or something else useful).
The scale of that game was different though, and we have to try to think more in abstract terms. Don't forget also that those trade routes to far away cities are going to pass through multiple trading posts! They are probably picking up goods all along the way from Rome to the frontier cities. To get the +5 food per trade route, you have to be using policy cards and/or a governor, which means that something is going on to make sure there is a focus on getting that food for those convoys. How many years does it take for a caravan truck to get from Rome to the farthest city? I guarantee they could not have picked up that food and kept it in cargo the whole trip!
Realism unfortunately sometimes has to take a back seat to game balance.
The scale of that game was different though, and we have to try to think more in abstract terms. Don't forget also that those trade routes to far away cities are going to pass through multiple trading posts! They are probably picking up goods all along the way from Rome to the frontier cities. To get the +5 food per trade route, you have to be using policy cards and/or a governor, which means that something is going on to make sure there is a focus on getting that food for those convoys. How many years does it take for a caravan truck to get from Rome to the farthest city? I guarantee they could not have picked up that food and kept it in cargo the whole trip!
Realism unfortunately sometimes has to take a back seat to game balance.