There are actually three major telecom companies making up 85%+ of the market share: Bell, Rogers, and Telus. Don't be fooled by names like Virgin, Fido, and Koodo, as those are just the "lite" subsidiaries of the three major companies respectively.

For supermarkets there is Loblaws, as you said. But, it's not like Sobeys and Metro are much better, they just keep their robber-baron executives better hidden.