This a discussion that keeps coming up a lot.
In the old days the fridges used to be three way. LP, A/C and 12V, now for some reason the fridges are only two way LP and A/C power. Why they dropped the 12V I have no idea as we used to travel with the fridge on 12 volt with no problems at all.
Now we do travel with the fridge on propane, but when fueling we always shut the fridge off. If you are in a gas station and the fridge lights up, if there was enough vapour at the fridge venting it could spark a fire.
My train of thought is the fridge does not know if you are driving down the road or sitting in a campsite with a 60MPH wind blowing over the vents of the fridge.
Happy travels and cold drinks!!