Darius I – 73rd Great Khan of the Illustrius Barbarian Horde, Duque San Lorenzo, Marquis de Feltón, Chief of the Zayante, Baron von Whaleyland, Lord Kennedy
As per the rules, cards used to pay the construction costs are out of play and placed under the wonder.You are misreading this. You pay the construction costs via resources, commodities, and money from your supply, then you place the card you drew from the pyramid under the wonder. You do not put the resource and commodity cards under the wonder. The resources and commodities can be used over and over again throughout the ages of the game. They never run out (although they are limited to a one use per purchase basis).