Oh, I guess a more in depth explanation is required…

You see, FFIX was unfortunate enough to be released right before the transition of consoles, and right after FFVIII. Most people were turned of the series after playing FFVIII, because they were pathetic idiot fan boys that had been deprived of there precious Sephiroth, or egotistical jerks that loved the original FF games on an unnatural level, and will put a bullet through there head before they succumb to change. What they didn’t realize was that FFIX was nothing like FFVIII (which I loved anyway) and never found out that FFIX was in fact a master piece. Not sure whether you can factor FF: The Spirits Within into that equation somewhere, but I’m sure that couldn’t have helped the game in terms of popularity. Thus the game never sold that well (Compared to FFVII and FFVIII anyway) so I'm not surprised that stores are less likely to stock it.

.: People are idiots.