That's because the NRT only looks for files directly related to Norton itself (and its installation). Lets say you were a Hollywood journalist and you wrote a story about Edward Norton, and saved that file as norton.doc.
That does not automatically make it part of Norton Antivirus, does it? So if the NRT automatically deleted anything with "norton" in its name, then you'd probably be a bit ticked off if it deleted your story.
Well this is kind of the same thing. These files have absolutely nothing to do with the actual installation of Norton anything and as a result the NRT isn't going to remove them. They simply exist for Acronis to use should Norton (or any of the other software in that list) already exist on your system. This is because those programs handle their files in a specific way, and Acronis needs to know that information so that when it backs up their files, it doesn't render them unusable.
If you don't like these files existing on your computer, simply uninstall Acronis, reboot, and then you should be able to delete them (as they should no long be marked as "in use"). If that doesn't work, then you should be able to do so from Safe Mode, or by changing their attributes manually.