Because of the way the footer information on topics is generated, we can't use <section> inside long topics. It may be that this is just a rule, or it may be that the stuff at the bottom should be wrapped in a <section>. The problem is that once you have a <section>, you can't have anything else at its level but other sections. So you can't have like this:

<section>
  <para>

  </para>

  <section>

  </section>

  <itemizedlist>

  </itemizedlist>
</section>

But you can have:

<section>
  <para>

  </para>

  <section>

  </section>
  <section>
    <itemizedlist>

    </itemizedlist>
  </section>
</section>