some hidden menu links are not hidden

Although these menu links are marked as hidden in my feature, they show up when I build up the site. I can disable them easily enough through the UI after the build, but why do they show up at all?

  // Exported menu link: navigation:sysstats
  $menu_links['navigation:sysstats'] = array(
    'menu_name' => 'navigation',
    'link_path' => 'sysstats',
    'router_path' => 'sysstats',
    'link_title' => 'System Stats',
    'options' => array(),
    'module' => 'planetmath_sysstats',
    'hidden' => '1',
    'external' => '0',
    'has_children' => '0',
    'expanded' => '0',
    'weight' => '-46',
  );
  // Exported menu link: navigation:aggregator
  $menu_links['navigation:aggregator'] = array(
    'menu_name' => 'navigation',
    'link_path' => 'aggregator',
    'router_path' => 'aggregator',
    'link_title' => 'Feed aggregator',
    'options' => array(),
    'module' => 'system',
    'hidden' => '1',
    'external' => '0',
    'has_children' => '1',
    'expanded' => '0',
    'weight' => '-44',
  );
  // Exported menu link: navigation:aggregator/sources
  $menu_links['navigation:aggregator/sources'] = array(
    'menu_name' => 'navigation',
    'link_path' => 'aggregator/sources',
    'router_path' => 'aggregator/sources',
    'link_title' => 'Sources',
    'options' => array(),
    'module' => 'system',
    'hidden' => '1',
    'external' => '0',
    'has_children' => '1',
    'expanded' => '0',
    'weight' => '0',
    'parent_path' => 'aggregator',
  );