Though I think the aborigines may use the machete a lot on the inland areas as well due to its versatility(chopper knife shovel). But really here there is generally enough deadfall/small branches that chopping to make a fire is not necessary, or can relatively easily be broken or burned into pieces. I once came across somone who had carried a hatchet into a remote campsite and was hacking away - the universal feeling from all the other campers was that he was nuts.
Over here pretty much anyone going into a desert carries a spade - for digging thier cars out. I have had to use mine on occasions for that reason.
I am of Aboriginal background , my people are the Barkentji mob , from around Wilcannia way , tho I spent a lot of time in the Kimberlies and inland northern WA and western NT with the Pitjinjarra people , and grew up with the Noongyar and Yamatji people . The only time I have seen people using a machete to dig , it was done by city people . digging is done with a digging stick , a cutting edge is just too valuable to abuse like that .
If you ask among the women anyway , they usually prefer a shortish crowbar , the shape and weight make them good digging tools , as well as decent weapons to use on each other .... another subject entirely tho . Im no expert in womens business tho and do not claim to be in anyway .
the most common knives I have seen used by desert people is a butcher knife for meat working , goanna , camel , roo whatever , a little folder / pen knife hi carbon blades are prized , for delicate carving and fine work .
Big blades , in my experience , were rare .
"blackfella" fires never really required firewood cut to length , when branches smash when you hit them together , or you just shove them in as they burn away . Hatchets are pretty common among the people who still do wood work , as big chisels more or less .
a ton of variables tho , there is no hard n fast rule that applies to any area really that I seen