Cast iron is very inefficient as a heat conductor which is its beauty. It takes quite a lot of fuel to heat, once hot it will retain heat for quite a while. It does very well on open fires and has been used on them for many decades. All pans have their place, aluminum, stainless, carbon steel, copper, all these came after cast iron. I think many use cast iron is a sentimental tool camping as much a functional tool. I wonder how many use it at home.
I leave my cast iron at home, I don't like the added weight and extra care it takes. I cook on the road like I cook at home. I will make any of the mother sauces for meals without thinking twice. My cooking pots are stainless with thick aluminum bottoms. I like the way they nest and cook, clean over all. YMMV