[JRTJH]

I would not go out on a limb and say that supplemental heat is "REQUIRED" to camp in cold weather. There are a number of scenarios where supplemental heat (usually electric heat) is not available to be used. Dry camping is one that immediately comes to mind.

While supplemental heat may be "nice to have" or may "make it more comfortable" (by not running the "loud" furnace) it is, by no means, a requirement for camping in cold weather.

Some RV's have more insulation and less air infiltration than others, so each situation is somewhat different.