That would be nice, but it is a real bother for some. Like me. I do like stories, writing stories, planning stories, etc but how can I tell what people are in that land? Moreover, it is (figuratively) "my" nation now and I can do whatever I wish with the population. It would add realism, sure, but this is CNRP. Its barely even realistic for another population to come out of nowhere and claim some land while there are people on it, especially when that population may have had the best technology in the world & logically would fight against the oppressors with those weapons.
Again, it would be nice to RP doing something to the local population so you can have your own people there. But, so long as this does not become a rule/generally accepted standard (aka unofficial penalization for not starting your nation like this) for all roleplayer's in CNRP, it would be adding another unnecessary step to making a nation. I'm not against the person doing it, they can do it by all means; so long as it isn't mandatory.