Even if carrying the unloaded, non-restricted, firearm downtown was legal, when there's more people around it would become more difficult not to accidentally break another law. For instance, if you accidentally point the muzzle at someone.
Also, if the police saw you, it may also result in them seeing you as a threat to their safety, which means it won't matter if your gun was legal or not. And if someone did get their hand slapped for shooting you down, it would be cold comfort for your family.
This man was carrying a perfectly legal whittling knife when he was gunned down by Seattle police.
Second squad car arrives.
Further to the above, you'd also need to check provincial and municipal regulations, as well as the criminal code. Just because the Federal Law doesn't prevent you from doing something, doesn't mean its not enforced differently at another level of government.
I don't even know what to say. That cop ####ING EXECUTED that guy. There is no other way to look at that.