While the law is federal, I have never been asked for a PAL by any LEO in AB yet. CO's will never ask.
I live in nothern rural Alberta, and I bet at least 1/3 of hunters have no PAL or POL and/or are using an unregistered firearm. I am not saying the RCMP are not concerned, but setting up a checkstop at any popular moose hunting road would guarantee 20 charges on a Saturday--and it hasn't happened yet.
I have told the story before, I was at the range one day, maybe a dozen guys there. An RCMP cruiser pulled in with a uniformed member planning to shoot his duty shotgun. 3/4 of the guys there cased their guns at the sight of the cuiser and stopped shooting and wouldn't shoot in front of him. I wonder why?
Again, wouldn't take much effort on the part of the RCMP to lay a lot of charges. But, they choose not to, so it does seem like the law is not being enforced.