FWIW, you should be able to remove that by editing the PAGE_CONTAINER template. I don't believe we use it for anything, but there's no guarantee it won't be used in the future or no guarantee it isn't used by developers, for some reason.
Out of mere curiosity, why would it be important to remove this - bear in mind we're not talking about branding now, we're talking about changing references in the code which effectively impact on nothing at all (and there are others, too, such as the directory where JS files are served from).