The number one problem (not mentioned) is opsec
I'm a civilian. I have no OPSEC concerns -- rather the contrary. If I'm in a survival situation, I want to be found.
I think the reason why we focus on fires is because we like them.
Don't underestimate the positive power of morale. If calm is the only thing that fire provides (besides warmth, visibility, water disinfection, and cooking) then it's worthwhile just for that in many situations.