Calgary is close behind.
Winnipeg has been the slurpee capital since 1999. (now being 2010)
Winnipeg on averages over 188,000 slurpees a month, even though its known for its coldness.
Kennewick, Washington, USA falsely claimed to be the Slurpee Capital of the World, later to be proven. The false claim uproared Winnipegers, to such a degree, that they got radio stations aware of the lie.