To cultivators, their weapons and their armor were their most valuable possessions. Generally speaking, when cultivators spoke of 'trading treasures' or 'handing over treasures', they were excluding the weapons and armor which they normally used! A Universe weapon which acknowledged you and was a good fit for you… such a treasure was incredibly hard to find. And how much blood and effort would have to be poured into a suit of Lifeblood armor, allowing it to grow over the aeons?
Other treasures might be valuable, but the loss of them would not have too much of an impact on Hegemon Winterflame's actual level of power. It would've hurt, but he would've bit his tongue and accepted. His weapons and his armor? Once those were lost, his power would dramatically drop.
"Yes, I want both." Ning looked at him. "I want all of your treasures! You must hand over every last drop of chaos nectar and every last chaos jewel, to say nothing of your Universe treasures."