Like many if not most, we run on the road with LP on and Fridge in LP mode. To fill the LPG tank, we have to turn its valve off. But the Fridge itself needs to be turned OFF also, since it'll attempt to re-light itself once the LPG runs out. Whether Flame or Spark, we don't want an ignition source at the Fridge. Same would be true of Furnace or Water Heater, but we don't travel with those on. Basically anything with a logic board for electronic ignition.
But to fuel Gasoline, I only turn the Fridge OFF. Jayco extended the gasoline filler way to the back of the coach. If they had not, the filler would be right at the fridge. There's probably an engineering/safety standard that dictated putting some separation between the two.