When it says that names themselves aren't copyrightable and that you can't get in trouble for mentioning them, that is one thing. I.e I can write an article and mention Marty mcfly all I want. That's not infringement.
If they named one knife after a character, or a side character, that may even skirt the law somewhat.
Naming an entire line of knives after the main characters of a series? That is just asking for trouble.
I don't expect that I could make a black knife and call it the darth vader, make a blue and white one and call it the r2d2, etc. without lucasfilm paying attention.
http://www.quora.com/What-are-the-l...r-a-famous-dead-person-or-fictional-character