Lablaws and Gt Cdn SuperStore and the "Green" discount grocery stores are all owned by Weston, which also owns Holt Renfrew. HR has actually carried Fortnum and Mason Christmas puddings and the like for many years. I still preferred making trips over to London in late November or early December to stock up on those mini-sized puddings and those jars of brandy butter!
Weston is owned primarily by the husband of the Ontario L-G, but a little bit my yours truly.
As for Canadian wines being in the plonk section of Tescos, I will reserve comment because I am already fighting too many wars on this board as it is...