Say you want to re-arrange information in a spreadsheet. If you simply copy and paste the rows or columns, they will overwrite the existing cells. Instead, you have to Copy (Cmd+C) then Insert>Copied Rows or Copied Columns — depending on what you’ve copied. This is not available via shortcut or context menu.
As an aside, trying to setup a keyboard shortcut for Insert Copied Rows in System Preferences did not work for me. Is there a solution for this?