Elder Kumu was indeed startled when he saw the list of treasures Yi Jue presented, but remarks like "might as well kill me" were meant as a joke. With his wealth, he truly could afford these treasures.
The only concern is that many treasures are invaluable yet unavailable. Although his wealth far surpasses Yi Jue's, the collectibles he possesses are relatively low-end resources, unlike Yi Jue, who has many valuable items.
This is related to his business skills but also his not-so-bright prospects for achieving a breakthrough.
Yi Jue's goal has always been to break through; after getting good things, she usually doesn't trade with others. However, Kumu doesn't mind; if his sect-mates or friends need rare resources, he doesn't reject trading with them.
