Typically, competition law, not just in Canada but elsewhere, is not really meant to address imbalances in bargaining power in how a large company deals with suppliers or customers. If a large company imposes unfair prices or unfair fees on suppliers or charges high prices to customers, that is not offside according to the Competition Act. What is offside is if you abuse your dominant position by taking steps to undermine competition and make it so the competition isn't working by raising barriers or excluding competitors.
It is a fine line between the two, but typically, competition law is not meant to address imbalances in bargaining power.