Why not give the chicks to other people to raise? (Assuming this story is true.)
Because they might not buy TYSON’S chicken if they had their own. Oh, and Tyson owns the chicks and can do whatever they want with them.
Because that does not reduce supply. Therefore the price would not go up.
Oviously Tyson has run out of ways to increase demand at the price it wants.
This is like OPEC reducing output.