Occur should use the region as input if it's active

[Tom]

If often happens to me that I'm perusing a buffer and I want to 
search for some word or phrase in it. To do this I simply select the 
text and use this code to instantly get occur matches of it:

    (defun my-occur ()
      (interactive)
      (if (use-region-p)
          (occur (buffer-substring-no-properties
                  (region-beginning) (region-end)))
        (call-interactively 'occur)))

Shouldn't the builtin occur do this? It's quite convenient and
efficient and in my experience most of the occur searches are
of these kind (searching for something I see) and it's less
often that I actualy need to type in the search term.