Why go through the hassle of brining food and having a customs agent ask you the same question six different ways? Don't bring food and just shop in Walmart or costco when you get to canada.
The reason is I will be camping for two weeks prior to my entry into Canada. Plus since I'm a wanderer, I really won't know exactly when I cross until the day before. So it will be hard to be completely out of food, left-overs and non-canned food before I cross. So knowing what I can or can't have will help me plan the couple of meals before hand to reduce the tossing of food.
My defensive weapon is a fire extinguisher. Non-lethal and scary as all get out when one is on the receiving end. As the person is ducking, you can always hit them with the bottle.