*Looks at copy of Half-life 2 and Metro 2033*
Unfortunately you have only used examples of shooters with crappy stories that only have a single player so they ship more copies. There are shooters that have good stories, shooters like my above examples of Half-life 2 and Metro 2033. Other shooters like Deus Ex and the Fallout games spring to mind or, if we're not just sticking to FPS's, Mass Effect one and two.
So there are shooters with good stories, you're just looking in the wrong place.
Unfortunately you have only used examples of shooters with crappy stories that only have a single player so they ship more copies. There are shooters that have good stories, shooters like my above examples of Half-life 2 and Metro 2033. Other shooters like Deus Ex and the Fallout games spring to mind or, if we're not just sticking to FPS's, Mass Effect one and two.
So there are shooters with good stories, you're just looking in the wrong place.