The societies that practice cannibalism do it for a reason. It was(still is) practiced by some tribes cultures in South America, Africa, and the Pacific Islands. The example that comes to mind is the Fore tribe of New Guinea.
In this case, it was a form of ancestor worship. Family members consumed the bodies of their relatives. Unfortunate side effect was that people developed a disease called kuru, which is kind of like mad cow disease. In case anybody is wondering, the government of New Guinea cracked down on cannibalism 20-30 years ago. A few cases of kuru still occur because of the long incubation period.
The other form of cannibalism has a much more sinister intent. People kill and eat their enemies during tribal warfare. It basically destroys the soul of the victim(or holds it hostage). No soul equals no happy afterlife. I believe that this form of cannibalism existed in New Guinea also.
The only people who would want to purchase Hufu are would-be serial killers, etc. Real cannibals wouldn't have the cultural incentive to buy the product, and even if they did they wouldn't have access. It's not like the average person living in a jungle village has access to a supermarket, or a credit card to go shopping on the internet.
Meat is basically meat. I would guess that human flesh tastes like the flesh of any other omnivorous animal. The reason that most animals don't eat humans is that most people are smart enough to avoid being eaten.