@Crissov, I give you the same challenge:
Yes, i know a HTML <section> supports this but even there I challenge you to find an example of where it is used that way. I think it’s supported by accident, an artifact of HTML’s XML-derived syntax (closing tags). Even if you find one, see if you can see that structure in the browser rendering. Unless the rendering/CSS applies borders, shading or indentation, it cannot show the end of a section without starting a new one, just like Markdown.
I think this also is trying to make Markdown behave like HTML/XML, whether or not it has any practical use.