I'm with Ian. Vinegar is used in the Northern States in cooking (not on fries)...as well as in cleaning. Oh yes, it's a hell of a disinfectant.
On the fries, ketchup (or catsup...does anybody call it catsup?) please. Pass the Heinz!
Speaking of food and Canada, I was reading
Uncle John's Slightly Irregular Bathroom Reader and several Canadian dishes are mentioned, including:
Poutine - French fries and a heap of cheese (or cheese curds) immersed in brown gravy
Trempette - Bread soaked in maple syrup and topped with heavy cream
Tire sur la neige - Heated maple syrup that congeals into taffy when served on top of fresh snow
Kraft Dinner sandwich - Macaroni and cheese on white bread, topped with ketchup
I guess Canadians do use ketchup, but perhaps more on mac and cheese and less on french fries.
After reading the dishes above, is it any wonder that the book is called
Uncle John's Slightly Irregular Bathroom Reader?