The biggest 'waste' of electrical usage/ money in winter camping in my experience is the water heater.
It is also almost always the cause of tripped breakers when running electrical heaters. Because you have no control when the water heater comes on. Many rigs I've seen have the water heater plugged into a normal wall receptical - which is on the same 15 amp circuit as the GFCI which controls the outlets in the bedroom area. Others have the water heater on the living room/ kitchen circuit. (Ours is on the kitchen circuit - if the water heater kicks on while the Keurig is making my coffee - tripped breaker.)
Running the water heater on propane avoids the sudden loads which trip breakers - and if you are paying for electricity - propane is almost always cheaper than electricity.
The only concern I would have is if the temps are steadily down in the teens or lower.
I've used propane once or twice a day to heat up water with night time temps down below 20 - but daytime highs came into the upper 20s and low 30s.
Also because the propane costs are usually cheaper than electricity costs - I use the propane furnace as the primary heat, and the fireplace and space heater as supplements.