I agree – we’ll be changing that in the next free version.
If you’re comfortable editing code, you can remove &hide_empty=1 here: https://github.com/tomusborne/wp-show-posts/blob/1.1.3/admin/ajax.php#L41
You can see the change we made here: https://github.com/tomusborne/wp-show-posts/commit/fdfe13b25893974a63a8fe0decf2672c85089540