Use menu name rather than ID number in CSS

I'm not sure if this is an actual bug or something by design.

In my custom theme, I'm using theme_nice_menu_primary_links like this in template.php:

$vars['primary_links_tree'] = theme('nice_menu_primary_links','left');

In page.tpl.php:

        <?php if ($primary_links): ?>
          <div id="primary-menu">
            <?php print $primary_links_tree; ?>
          </div> <!-- /primary-menu -->
        <?php endif; ?>

I have another menu of which I'm trying to place into my theme in the same way, but of course using theme_nice_menu:

$menu-tools = theme('nice_menu',0,'menu-tools',0,'down');
$vars['menu_tools_tree'] = $menu-tools['content'];

In page.tpl.php

            <?php if ($menu_tools_tree): ?>
              <div id="tools-menu">
                <?php print $menu_tools_tree; ?>
              </div> <!-- /tools-menu -->
            <?php endif; ?>

Some of you may notice right away that I'm calling this other menu in the same way theme_nice_menu_primary_links calls the primary links menu, by using a 0 as the $id, thereby bypassing the need to configure a block.

The pro of doing this is that I don't need (and Drupal doesn't need) to deal with blocks to render a menu. The con of doing this is that the HTML that's rendered assigns the same CSS id to this menu as what gets assigned to the primary links, a minor detail but still a source of confusion.

  <div id="primary-menu">
    <ul id="nice-menu-0" class="nice-menu nice-menu-down">
...
  <div id="tools-menu">
    <ul id="nice-menu-0" class="nice-menu nice-menu-down">

Not being familiar with the code, I don't understand why it would be necessary to deal with the blocks subsystem when working with raw menus. The project page for Nice Menus implies that using blocks is unnecessary: "For themers, it is also possible to theme a menu as a Nice Menu directly by using the provided theme functions so a block is not necessary." Yet for this issue with the CSS id, one would still need to configure a block that isn't used if one wanted the CSS id to be unique.

I don't know how much it is worth it to fix.