Yes, and of course, there are many people who visit communities and would take advantage of any subsidy that was to the retailer, so you're not always targeting the right people with a subsidy to the retailer. You're targeting everyone who eats in the north, rather than those who actually live there and eat. That's one thing you might take into account.
The concept of fairness would apply there, too, and the record of the sale of food would be much easier for the department. You would have food that was being delivered at cost in the community, so the cost of food would be well understood. The subsidy would be with the consumer. The consumers could then purchase the items they need to reduce the cost of their overall food bill.
Why would we necessarily want to stick it with the retailers so that we make an artificial system of delivering food into those communities?