This location is unfortunately overpriced and clearly designed to part tourists and their money. The store is small, located in the bottom of the terminal building. You couldn't do a full shop here (they have a fairly limited selection of stuff) but it's great if you're just picking up a few things.
The one thing this Sobey's is great for is lunch - they have a made to order sandwich and salad bar, as well as hot food (chicken, potatoes, veggies, soup, wings) and pre-made salads and sandwiches. They also have a huge selection of gourmet and traditional salads.
I also really like the sushi - although 6 pieces for $6 is expensive, it's cheaper than a sandwich and the portions are quite filling. Oh, if you're looking to complete your meal, there's a wine rack located just inside the store for all your vino needs!