Life is a matter of making choices. Most of us weigh the situation and the possible consequences of same, then we make a decision. I do the same with driving with the propane turned on, which I do and have since purchasing my first RV in 1974, 39 years ago.
The most dangerous thing any of us do with our RVs is to drive them on the public highways of North America. Last year in Florida, over 4,000 people died from auto accidents in Florida. Now we all know this is a possibility, that could happen to any of us when we get in our RVs to head out on a trip. But we still all go and just try to be careful. Generally for most of us that works. But how many of the 4,000 people that died in car wrecks here in Florida, thought that morning as they were getting into their cars, "this would sure be a nice day to die."
I grew up using large amounts of propane as most of the fuel we used on the ranch was propane, we ran trucks, grain dryers, irrigation pumps, heated the house and out building, Mom cooked on gas, dried clothes, etc. Propane seems to concern people more than say does gasoline, because propane is a gas at normal atmospheric pressures and temperatures and you can't see it. Spill gasoline or diesel and you can see it on the ground, but not propane.
Since I drive a diesel truck, I am not as concerned with refueling and shutting off the fridge as I would be with gasoline. In one of the arson classes I took one time, a weekend assignment for the class was to try and figure out some way to ignite the fumes off of a pan of diesel. No one in class came up with a way to do it. The instructor was trying to get the point over to the class that when we were investigating a fire and the owner claimed he was washing car parts in diesel and a hot ash fell off his cigarette fell into the pan and ignited the diesel, to make sure we looked more deeply into the fire origin.
So if I am fueling at a diesel only pump, I leave the fridge on, if someone is using gasoline on the other side of the pump, then I will turn it off. Now flash fires from open gasoline are fairly common a call for the ambulance to transport someone to the hospital.
I remember one time a group of us campground "experts" were visiting and one old fellow was claiming that anyone that drove with the propane turned on was an idiot. However at the same time he was lighting up a cigarette. All depends on what a person considers to be too dangerous with little benefits. I have over 3,000 hours of Alaska bush flying experience, which I considered to be worth the risk, though it wasn't for a number of people I knew doing the same thing, but no way could you get me to bungee jump, as the benefits just aren't in it for me.