HK heavily relies on financial and tourism industry, goods are mostly imported, commodities purchased in HK as such are fluctuating and varied according to imported prices which are vulnerable to external economic environment.
Canada is a well self-contained country. It has a huge auto industry, a huge domestic agricultural industry, exports oil. The range of jobs are v different from Hong Kong, much more diverse, can suit people's different needs and talents.
Of course, one can earn more in HK for certain as it has a mass "free" financial market, so money comes but also goes.