At one time, several fridge models were equipped with a timer that automatically shut off the burner for approx. half an hour after the vehicle engine was shut off.
Burner operation was restored as soon as the vehicle engine was restarted, or after the timeout period had expired (on the assumption that the RV was parked for some reason other than a fuel-up).
There was also a product available on the aftermarket ("FlaimOut") that did the same thing - It could be retrofitted to most 2- or 3-way fridges with electronic burner ignition.
The biggest downside with this scheme is that it requires a dedicated connection between the fridge and vehicle's engine ignition switch - which could be particularly unwieldy on towed RVs that don't have any spare pins available on the hitch electrical connector to pass this signal between the TV and trailer.