I don't really see what's fake about the image, other than the price on her sign. Everything else about the pic is alright. She looks like the same girl in the DVD, the DVD is real (according to the link to the DVD's info that someone posted), there are clips of the DVD on YouTube, and obviously if she's not that popular, of course all those guys in the pic would simply pass her by. Not to mention, it might even just be a misleading photo... there might be a whole bunch of fans right in front of her (behind the photographer), which of course we can't see. Likewise, the guys behind her wouldn't know who she is, because they only see her back. Or, maybe she JUST arrived on the scene, so of course no one had time to even notice who she was yet. But most of all, you gotta keep in mind that thousands of people walk by Akihabara station every day, and not all of them are idol/singer fans. And not all idol fans like every pretty idol/singer, so even if a quarter of the guys in the scene are fanboys, hardly any of them would know her, much less be such fans that they'll rush her for an autograph. See, there are several possibilities that can make this a realistic photo. And Konami doesn't only produce videogames (look at its Wikipedia entry), and is big on music (that's why they even make the most popular musical games), so Konami making DVDs for singers shouldn't be too surprising.
As for the price on the DVD, the real price is supposed to be 3500 yen according to the link. Whoever shooped the photo ONLY had to change the price on the DVD to emphasize the sadness of Saori's face. That is, the person saw the pic, thought "She looks sad... why? I know! I'll edit the pic so there's a reason she's sad... *shoops*... There!" And finally, she doesn't even look that sad. She might just be momentarily looking at the ground after being tired of looking at people.