To make it easier to transfer one postal address from one contact to another.
I suggest to add a button "Copy" (either on the display view called Location, or in the popup where addresses can be entered), and to add a button "Paste" in the popup. (Or just the way that e.g. URLs are automatically pasted when a dialog window opens; if there is a postal address on the clipboard when opening the "New" address dialog, paste the clipboard there.)

Reproducible: Didn't try