well, some guns do. Handguns, assault rifles, smgs, etc are only good for killing people. However, long guns do have other uses... like killing varmints. Not an inconsequential use either, if you live in rural Canada and farm.
We've had a hell of a time doing gun control legislation that can effectively deal with the contexts of rural and (esp big-city) urban Canada. One reason why it's so difficult is because of the federal nature of our system. However, there are some fundamental disconnects between the two communities. In fact, on a legal level, there are some fundamental disconnects between the two: cities belong to the province, not to the federal government. This makes creating that kind of legislation difficult.
Incidentally, the main jurisdictional issues involved are that gun control decision making should be municipally based, but neither municipalities nor provinces can make crimes: only the federal government can. However, the federal government doesn't do summary and/or civil stuff very much (outside the setting of standards). Since carrying a loaded rifle in downtown Flin Flon might need different treatment than one in downtown Toronto (in Flin Flon, you might be taking out the family of prairie dogs that moved into your backyard this spring, while in Toronto if you're just cruising around with a loaded rifle you're probably looking for the bank, or worse yet the bell tower), it's difficult because no one particular government has all the tools available to it.