You really think there is observable behavior that Europeans don't understand trade?

You really think there is observable behavior that Africans don't understand duty?

Trade doesn't really rely on any of those things. It just relies on cost-benefit analysis. The currency of fear can be just as likely a factor in that analysis as fairness or honor.

Only fear of other things that stimulate your need to trade. If you fear the buyer or seller to the point that you feel like you have no other choice but to exchange something, that's not trade, it's coercion.