Two things:
1. Alberta teachers have received wage increases of 5% per year in recently settled contracts (the past 3 - 5 years). In MB, we've never gotten more than 2 - 3 percent increases. Nurses in MB. took a wage freeze a few years ago. I realize I'm only looking at a couple of sectors, but I think the idea that MB. is union friendly while Alberta is not is somewhat misplaced.
2. Most people go to Alberta because the oil fields are the only place in Canada where you can earn good money without having a degree. Of course they could find employment at home, but nothing can compete with that oil field pay cheque. Seriously, if some one running a manufacturing business paid their employees oil field wages, they wouldn't be in business very long.