YOu could add something to Savas list:
The Zoners are "normally" not out for war and that is the message tehy sell to everyone - they claim to be peaceful fellows who want to be left alone and not bothered by the big players. These big players tolerate them and their schrewd ways of living as they pose no threat to them and provide at least some usefullness to some of them. This "i don't really care all that much " stance might very well shift(or should have shifted already) if suddenly the houses see such a massive armament of the Zoners. What do they arm for if they don't want to be bothered and don't bother anyone? The unspecified Nomad threat? What if they do it for something else? Would you risk it?
==> aka look at states trying to set up nukes and who are equally untrustworthy as the Zoners are to the houses....people don't want others to be armed if they can't avoid it even if the claim is that it is purely for defense...say no to caps