Apparently the logic is that it's cheaper and uses less energy to maintain a low temperature than to let the temperature and humidity rise then have to pull it

Apparently the logic is that it's cheaper and uses less energy to maintain a low temperature than to let the temperature and humidity rise then have to pull it down again. I can believe that: dry air is a much better insulator than humid air, and if you want it as dry as possible, that means going as cold as possible.