Instantiating an uGUI element - not parented to canvas

It seems that when you instantiate an uGUI element, it’s not parented to canvas… Is there a way to specify that the element is to be in worldspace without needing a canvas?

Nope. The canvas object contains the Canvas component which is required for uGUI rendering. So you have to parent the item under a canvas object for it to be render. The fact that the object is in World Space does not remove the need for a canvas object.