Blu-Ray query???

[goubs]

Hi there,

I was wondering why if Blu-Ray discs can store so much data, how come titles like Blade Runner: Final Cut and Pirates of The Caribbean: At World End come out on double disc sets which raise the prices up further on an already expensive format. Why can the not fit on a single disc.

I believe I remember being told that you could fit 24 half hour episodes on one Blu-Ray disc and yet if I'm not mistaken Smallville was on a 6 BD set.

Does anyone know why this is???

Thanks