I'm interested in discussing this as well. 
Birds naturally gorge themselves for upcoming migration, or once it gets cold out. If you've ever hunted geese over a cornfield a month into migration, you'll see some extremely large livers! It is a natural process.
There are a couple producers who don't gavage, and some still good ones that do, but their ducks have a happy life. Some offer a chilled environment so the ducks will feed themselves.
I have ordered Grade B from several different foie producers, and it's normally $35-$40 a lb, but in season, grade A can run you over $100. 
It doesn't taste a thing like liver, just vaguely.