Page used as Blog posts listing sitemap issue

If someone could explain the following issue for me.

Various themes give us possibility to set a page as a blog page, using archives template to display all the posts (instead of simply linking category). There are few advantages of that obviously… what bothers me though is that when I use a page as a blog archives page – this page is getting included in both posts and pages sitemap?

Am I saying ‘hi’ to duplicate content issue now? Is that a normal behavior or is it a bug in XML Sitemap module?

https://wordpress.org/plugins/wordpress-seo/