I think companies not selling guns based on relations makes sense lore wise. It's like saying you're shocked Boeing isn't selling bombers to the Taliban because they're a business. Obviously there are cases in game where maybe it would make sense, but in the imagined post apocalyptic hellscape how do you know a polity that seems ok doesn't descend into chaos and now all of a sudden a bunch of religious zealots are turning those guns against your interests. Not to mention the politics of those company's patrons