Conversation so far:
what was the importance and uses of bison for the Blackfoot Confederacy?
The Blackfoot Confederacy's main source of food on the plains was the American bison, the largest mammal in North America.
how did the Blackfoot Confederacy use bison?
The Blackfoot Confederacy's main source of food on the plains was the American bison, the largest mammal in North America.

Question: if it was sacred, why did they eat it?
Self-contained rewrite: if it was sacred, why did the Blackfoot Confederacy eat bison?