Tuscani01, I know that you work in Store Support (Retail City ?) for Canadian Tire but your information here is not correct. Lumsden Brothers, a Division of Sobeys, was the original supplier of food into the pilot stores on the food test except for those products (e.g. commercial bakery, dairy) that go direct store delivery into grocery stores. Sobeys pulled out of the test very early into it for internal political reasons which required Canadian Tire to scramble for an alternative source of supply which is how they ended up working with their current supplier whom I believe is Karry's.
It is also fairly well known in the industry that Sobeys and Canadian Tire worked together between 2004 and 2006 on a number of initiatives including the development of a joint store "Supercentre" concept that got as far as a store layout and drawing stage. One of the outcomes of this work was Sobeys participation in the "Q" store concept as well as the Sobeys-Canadian Tire gas promotion that ran for a while during that time period.
It is hard enough for different functions and subsidiaries in any company to work together but almost impossible for a joint venture between related companies to work productively over the long term. I know that this was one of the issues that Sobeys had during the "Supercentre" discussion as they had a failed JV with K-Mart in Atlantic Canada many, many years ago. However, it is a moot point, as there wasn't a major grocery store operator that was interested in supplying the stores let along something as complicated as a JV.