Plugin Categories Leaking Into Custom Menu Widget

On a site I am hosting I have created a custom menu and in that menu I have added just categories for the menu to display.

I noted that when I published this menu it has appearing in it extra items for the shopping cart that I did not publish in that menu at all.

I also noted that it was related to one of the menu items that is a blog category and if I move that blog category then all those items move along with it?

Some how it appears that the category when added to the menu pulls in default marketpress links for :

Products
Shopping Cart
Order Status

You can see it being weird here :

http://jesperlowgren.authorsite.org/news/

and I have placed the category that is somehow pulling these marketpress links in at the bottom of the News Categories widget on the right sidebar.

Why is this happening and how do I stop this from happening?

Thanks
Chris