Sobeys (ON) and Bonus Air Miles
Sobeys (ON) has a 3-day offer: spend $150 on gift card and receive 200 bonus Air Miles. (It's printed on the top right of the front page of the flyer.)
I bought several $150 gift cards, each in separate transactions. The fact that Sobeys gift cards can also be used at FreshCo, Foodland and several other grocery stores makes this an attractive deal.
200 Air Miles = $21.05 in future grocery purchases
So, it works out that, for every $150 Sobeys/FreshCo/etc. gift card, you will be getting $171.05 worth of groceries! :)