In dishes that actually get eaten - I have always seen ghost peppers and the other death peppers mixed in with things you make in large batches like chili as AggieChemist mentioned.
When I lived in Albuquerque, they had a fiery foods festival every year and you could sample all kinds of different things made from just about every chili pepper you could imagine.
I do not remember if they were made specifically from the ghost/scorpion/reaper, etc. There were a couple jelly's and chili oils that were both great and edible. I would not imagine they used very much at all. The heat was down in the jalapeno (or slightly above) region after made into jelly or oils.
The majority of the spicy jelly's/jams were raspberry and I do not know what that is the most prevalent flavor.
*** wear gloves do not touch your pp or get frisky with anyone until you have thoroughly gotten all of the capsaicin washed off.