Moving cities, factories and fortifications. (Little Upsilon)

I have looked at other peoples set ups. I have noticed a lot of people are moving their stuff around in certain configurations. Does moving items, such and fortifications to your boarders and cities and factories around your capital help at all, or is it for aesthetics?

Mostly aesthetics, although it might take a little extra time for military land forces to cross lots of empty space before encountering your cities. Also, some people move objects to "claim" territory in a neighbor. (Game quirk: the digital borders of countries dont align perfectly with the maps, so you can sometimes place one of your cities across the border in your neighbor or vice-versa.)