Here is a resource created by CfAT, that explores different housing in remote Australia. There is a perception that rammed earth makes the rest of the structure susceptible to white ants, so I don’t believe it is common.
In terms of hempcrete, adobe and other non-traditional building materials, if there is a cost benefit argument to be made, it should be explored. Transport costs will always be a factor whether using concrete or other materials.
Hope this helps you in choosing your direction,
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