Originally posted by TheAbominatrix
It may be possible that someone on Ebay is selling the disc from Anthologies on it's own, as opposed to both games together.
Or it's FF6 PAL. In Europe, FF6 PSX was released as one game with nothing else with it (well, it had FFX demo, but I wouldn't count that, really). FF Anthology Europe had FF4 and FF5 together.