That's what I was told and what I used to think. But the emigration officials at Edmonton said that if I was directing a shoot, I didn't need a work permit, but if I had my hands on the camera, I was displacing a Canadian worker.
As far as the parks go, I've heard some horror stories on other forums about officials harassing photographers and threatening to confiscate their equipment. There is certainly no way to tell a professional from an amateur by the type or size of their equipment. I have always thought that if I can shoot from a spot that anyone traveling to a park can shoot, that I don't harm the park or the park experience for anyone else, and I'm not using a crew, models, or props, then I should be able to shoot without a permit. That is not the case in the U.S. however. In the western U.S. National Forests and U.S.F.&W. Wildlife Refuges, the intent to make a profit (whether or not you ever do) is the test. If you intend to sell an image from a shoot in these areas, then you must purchase a Special Use Permit. The fees for the Special Use Permits are determined by each individual area manager and can vary a lot. One National Wildlife Refuge charged me $100 for an annual photography permit while a National Forest (to remain nameless) charged me $150 per day. I want to do everything legally and don't want to wind up in a Canadian Park and find out it will cost hundreds of dollars a day to photograph.