Licenses? I don't know what the problem is. You could invent similar names in a few minutes.
Money... pure and simple!
It would seem a little 'unrealistic' to rename them Clock, Sand Sparrow, Suzi and BigMac-10, so it would seem sensible for the creators of such travesty to cash in!
I wonder if you need a seperate license to use a nuclear bomb in a game, on that point, does the British Gov require you to license the name 'Trident' when used in conjunction with a nuclear themed based game?
If so, I'm going to create something that kills loads of people, and license it for games! :/
Scratch that idea, I've just thought, Red and his 'Guess the engine' forum game beat me to it! ;) <--- Notice the wink
Dabz