This most likely has been asked elsewhere, but after a bit of searching I have not found it.
A link would be sufficient, though it seems odd regardless.
Basically on the main page (main menu item) I have it setup to use easyblog frontpage layout. However if I add anything after that like site.com/dfherthdsgfbd it goes to the frontpage layout still when it "should" go to the default Joomla 404 page.
I am sure there is a setting somewhere, but if there is no posts and it has no matching item, by default it not showing a 404 page seems odd to me.