Cue NRA management getting its panties in a bunch and encouraging more "video games (specifically this EA title) are the cause of all violence in the world" from elected officials in their pockets.
You just hit on the REAL reason EA won't pay the royalties. Every time a horrific firearm related incident happens the NRA (which is basically run by gun companies) blames everyone (video games, movies, music) except themselves. This is EA sticking it back to them.
If they successfully defend their case then all other game publishers will follow and they will have hit gun makers in the pocketbook.
Good on EA.