Four Corners - Supermarket Power, page-12

Guy in the video seems to be treating profit and operating margins synonymously when they are very different. I dont think the coles CEO was referring to transportation costs etc as this guy suggests, I believe she might have been thinking in terms of capex as well as some other legitimate business costs which from my understanding dont show up under the operating margin.

I dont know the capex differences between UK supermarkets and Australian, however If the capex to run a supermarket in a low density area (which presumably has lower sales etc) is similar to the capex in a high density area, the low density supermarkets need higher operating margins in order to regain their investment and make a similar profit to the higher density supermarkets.