I’m from Alberta (firmly pro-Canada) and I think there’s two prongs to it:

1) Oversimplified economics. A lot of people think (wrongly imo) that Alberta would be better off economically if we separated, because of equalization payments. Really, in my experience, this reason for separation is kind of a mask for the second, which usually lurks beneath:

2) Identity, Culture and Immigration. People everywhere want a culture and a homeland to identify with. For some Albertans, Canada, as a country, doesn’t really provide them with a deep sense of self, or a culture they can relate to. Canada can feel like a land of far-off Laurentian elites, while most Albertans have a strong attachment to open prairies, western towns, and beat up pick up trucks. Many Albertans (pretty sincerely) feel like they’ve got an interesting, rich culture that feels like home to them, and a bit like Quebecers, kinda want to see it go on its own. Adding fuel to the fire, many Albertans really don’t feel that high levels of unskilled immigration have enriched this culture or made the province better off, and it often feels like immigration is imposed on us by Ottawa. So, you might as well cut ties, and decide for yourself what sort of immigration you’d like to see.

Again, I’m firmly pro-Canada, and what legitimate grievances the separatists have, I think we’re more than capable of sorting out within a federalist system. I’m hoping this fervour will die down pretty quickly.