Is the Everlasting Silver not available with Nightfall on the EX? if yes WHY?

[AgostoMortal]

I like this color the most, specially with the Nightfall package but I don't want/need the SX, looks like this color is not available on the EX with Nightfall but it is on the SX (with Nightfall)
what is the logic behind it, and why are some colors $485 and some other $0?
thanks

 

[maridi]

On Failcat, you can't even chose an EX Everlasting Silver with the Nightfall. So, there haven't been any made like that. The same with Sangria. Those two colors are only being made in Nightfall on SX's. I don't understand why not, since the Nightfall Edition is available on the other colors in EX's.
Good question about the color upcharge.
It seems like pearl has always cost more, but even with the Toyota Highlander, their Moondust (light blue) is extra. Maybe someone that knows more about paint can answer this question. I can't understand how a different color of paint could cost that much more than the others, but maybe I am missing something.