The Aborigine maintain the ancient traditions of their ancestors. In this traditions there are spears instead of guns. The current lack of guns does not mean they do not have criminals among them. The battle of good and evil is common to all cultures, with evil willing and able to cheat by any means. Now, their cheating is limited by the ancient traditions.
The elders would prefer to deal with their criminals in the old fashion ways of the ancient weapons. Guns are a wild card. Everyone knows that criminals are less likely to follow the rules, including the traditions of the Aborigine. This new wild card can become a future problem for the good people.
The result of an introduction of guns, could cause the criminals to ignore the limitations of their traditions, thereby getting too powerful. The good will be subdued, since only the good people will continue to use the harder standards of the old ways. This may be less about gun control, and more about being proactive to the needs of future criminal control. Guns could make hunting easier, but the criminals may extrapolate and exploit this.
If you go to any large American city, especially those controlled by the Democrats, gun violence is done mostly by criminals. It is not done by hunters who own guns. The line is between good and evil and not just guns, as the leaders of the worse cities extrapolate.
In the USA if you ban guns, the good people will comply, but the evil criminals will not give up their advantage. They do not follow the law. They will still look for and find what they need on the black market.
The Aborigine are not there yet, and would like to nip this in the bud, so their criminals will only use spears, clubs and knives. These old weapons tend to cause less death, being so close and personal. They do not wish the criminals to upgrade to the impersonal distant natures of guns, where even the weak bottom feeder criminals, become an overcompensating threat.
Guns are inanimate. The evil heart of criminals is the problem, since to them the ends justifies the means. The Aborigine elders understanding this and wish to limit the future means of evil. The old ways have worked for millennia to help maintain a balance.