1) traders might be attacked by other civilizations and looters
2) They may disagree upon the pricing and the worth of traded items
3) One may want to get rid of a item, another may not want to buy it, resulting in hatred and eventually war if it becomes too 'aggressive'
hope this helps
A person, typically one more remote than a grandparent, from whom one is descended:
They must enlist for the U.S. Military.
