The Space Merchants is a sci-fi classic about an advertising copywriter, Mitch, in a future where advertisers essentially rule the world. The lowest classes, consumers, scim proteins off scum ponds to feed a giant ever growing blob called Chicken Little. Chicken little is constantly having chunks sliced off its body to be used as meat. Mitch is eventually caught up in s double cross linked to the Consies, a conservationist organization who the corporate world view as terrorists, and a competing ad firm.
The Space Merchants feels a lot like Kurt Vonnegut's Player Piano. Also it was clearly a huge inspiration for M.T Anderson's Feed.