Before you skip everything in this video and run straight to the comments, understand the question: Many (not "most"; not "all") shooter video games feature licensed, real-world firearms. Gunmakers are compensated for the appearance of their brands as much as the NFL Players Association is paid for its members appearing in Madden. Does this present a moral choice to a video gamer?
This is not equating video game violence to real-world violence. The narrator of this piece, Mike Rugnetta of PBS' Idea Channel, explicitly says so. But if you are disposed against the US firearms industry and its chief lobbyist, the NRA, which uses video games as an intellectually dishonest diversion in its argument against any form of gun control, you should consider that which you buy.
Yep, some games feature all the violence of Medal of Honor with none of the real world weapons. Think Halo. (Think even more over-the-top, like Bulletstorm. Does anyone make an exploding-charge flail gun?). Electronic Arts also has challenged the idea that some appearances of real-world military vehicles in video games requires the consent of their manufacturers, so who's to say this wouldn't extend, in some uses, to firearms. There are other edge cases, too; not every game featuring a gun is money paid to a gun maker.
Still, for conscientious gamers, the most troublesome aspect of a realistic shooter may not be that it "trains" or desensitises a civilian to the use of a real, military purpose assault weapon. It's that buying those games helps finance the lie that they do.