Half the world's population - 3 billion people - cook over open fires. It's not "traditional societies" (whatever they are!!), it's every second person on the planet.
So a few bushcrafters cooking oatcakes on a hobo stove is really, really not going to make much difference to the overall picture.
Can't disagree with that, but Its not the overall picture that's under discussion.
Its very localised impacts on rare saproxylic insects that have specialised dead wood requirements, and the principle of carrying out a non-essential activity (hobby fires) that is removing some of that resource.
Once a population comes under pressure, for what ever reason, then previously insignificant activties can be come significant. Hence, the concern about burning even small quantities of wood. For the overall picture we also need to consider the broader environmental impacts of using alterntaive liquid fuels.
Having said that, although that seems to have become the main thrust of the discussion, this wasn't really part of my original question.
Graham