Why on earth would would the Coalition turn a blind eye to traders, the lubricant of capitalism so to speak? When traders aren't directly aiding the Coalition cause, they are undermining it by the very nature of what they do.
(And please, none of that "We are like China, and also friends with all, while also being archenemies to a bunch of things and establishing trade and forging alliances with monarcies"-stuff. That roleplay doesn't appeal to all.)
So is the reason that the folks at the Coalition have a particularly kind heart towards strangers and bitter political/financial enemies?
Is it a balance thing? That life's too hard for traders?
A player thing, that it's more fun to play the good guy, contrary to what the existing structure suggests?