Trying to understand Refrig fans - inside and out

Our outside fan in the roof vent is thermostatically controlled, so it only runs as needed. Our interior fin fans, two sets of two, cover almost the entire fin section, and run continuously while the fridge is turned on. Since adding the fin fans, the inside temperature is very consistent top to bottom, and we can run the temp setting at a lower number (warmer setting) than without them.