They dug up tons of rotted beef that had been culled, (supposedly ruined for resale by dumping a bunch of ashes and other stuff on it), before being buried. Then they made lots of hot dogs and sausage that they sold at the food concessions.
During the 1970s, a Quebec government inquiry into organized crime discovered that companies linked to Montreal’s powerful Italian Mafia were supplying meat to the city’s world’s fair held in 1967. The probe also found that most of the wieners and burgers sold to the Expo concessionaires – 400,000 pounds to be exact – was unfit for human consumption. A butcher who worked at one of the Mafia-controlled meat suppliers provided the inquiry with his recipe for a batch of hamburger patties: 20 pounds of turkey giblets, 40 pounds of beef, 60 pounds of horsemeat and seven or eight pounds of protein. He also admitted that some of the meat had been “recycled” from waste supplied by a local abattoir.