Including their brandname chains:
- Atlantic Cash & Carry
- Atlantic Superstore
- Axep
- Bloor Street Market
- Dominion
- Les Entrepôts Presto
- Extra Foods
- Fortinos
- Freshmart
- L’Intermarché
- Loblaws / Loblaw GreatFood / Loblaws CityMarket
- Lucky Dollar Foods
- Maxi / Maxi & Cie
- NG Cash & Carry
- No Frills
- Provigo
- Real Canadian Superstore
- Shop Easy Foods
- Shoppers Drug Mart / Pharmaprix
- SuperValu
- T & T Supermarket
- Valu-mart
- Wholesale Club / Club Entrepôt
- Your Independent Grocer / Independent CityMarket
- Zehrs Markets
Yes there are other big oligopoly chains like metro, Sobeys/Safeway, Pattison, but I think it’s best to start with one major chain to see how much coordinated action can affect them.
I’d wager it is, or was, a loss leader. Its position at the very end of the store has to be strategic to make you look at everything else on the way.