In my community (and in many northern communities, First Nations or not) the price of pop and alcohol is the same or less than in urban centres. Healthy foods like fruit, vegetables, fruit juices and milk are typically 250%-400% what you would pay in urban centres.

If you want to look at why northern communities consume more "junk food" than other urban/suburban centers you might start with why the bottlers subsidize pop and alcohol shipping.

My family is fortunate that my wife and I both have jobs, and can afford healthy foods, but we're still just living paycheck to paycheck. My sister-in-law isn't so fortunate, while her family diet is high in wild seafood (poor her, right?), she can only afford the cheaper processed crap high in empty calories, salt and sugar. Others are worse off than her, and their diet is dominated by low-cost, low-value food, because as that commercial alluded that impoverished people must make a decision to either feed your family or buy some heating oil