There's a problem there too if that what the law actually says. (I'm taking your word for it.)
What's wrong with carrying a knife with the intent to use it for self-defense, and therefore as a weapon? There's no problem in my book. Heck, I'm in favor of concealed carry of firearms, which would be a weapon.
It is my understanding that in Canada it is illegal to carry a knife for the purpose of self defence; it would be considered a weapon in such a case. I'm no lawyer or expert, but this is what I've come to understand from others.
The
law defines a weapon as "any thing used, designed to be used or intended for use (a) in causing death or injury to any person, or (b) for the purpose of threatening or intimidating any person and, without restricting the generality of the foregoing, includes a firearm."
Not arguing whether this is right or wrong, but it seems to be the way it is.