[Culverin]

Chinese Pig livers = leftovers from normal pigs we eat.
Foie gras = Specially farmed.

They are super force fed, this takes effort, care and time in order to do it.
Ditto with knowledge on how to properly run a foie gras farm.

Demand isn't super high, but supply is even lower, so that has made the price quite high.

As for how much you pay in a restaurant, places that would even serve foie gras in the first place are usually uppity so you'll get a premium.
It's considered a high end item, thus more premium.
My steaks are always screwed up when I eat out, and I'm thinking it'll be the same for foie gras, yet another reason i'm searching.

Please keep an eye out guys!