I've tried the Steam forums with this to no effect.
I have purchased a house inside the city and it have a food barrel with tons or dried meat inside. All my miners in the area were going there for food and it worked fine for a few in-game weeks.
Then I created a small outpost to the SW of the city, with just mining facilities and a food barrel. I noticed that food there was disappearing at an alarming rate, then I noticed that my miner by the city (for instance the one by the cursor in the screenshot) was also running to that outpost to feed. It is way farther than the one inside the city. While I appreciate the workout, I'd rather have them do their job more efficiently.
Also, another guy is mining the copper node by the other Squin gate, to the NE (BTW, there is a second copper node a few meters away, but it's on a steep side of the mountain and unreachable), he's the blue dot to the E of the city. This guy is somehow managing to starve on a regular basis, even though the food store inside the city is well stocked. I have to manually walk him to his feeding barrel. Again, this never happened during the few weeks I spent with just the city building as asset, before I made the tiny outpost on the other side of the city.
So what's the algorithm for getting food? I was expecting it to be to go to the closest one, but apparently it's not. I am planning to set up another small outpost to the North of the city, and I am worried that it may make their tiny little AI brains go boom.