I've had this issue for years. I can't recolor a group of objects with the eyedropper tool.
To be clear: I have one object that is blue and to the side of that, I have two objects grouped together that are yellow. I want to recolor both yellow shapes to be blue. So I select them, then take the eyedropper over to sample the blue object, but it doesn't recolor either of them.
I have even tried using the shift key with no results.