I bet 90% of any of this is because the market is saturated with placed to buy groceries.
Besides Tops, Wegmans, Aldi's, etc... there is BJ's, Sam's, Schwans and, the guy that drives a while pickup stopping in selling frozen fish/steaks, so on.
There are only so many people in the area which means there is only so much money to be spent on groceries. Everyone eats but there is still a limit to how much 900,000 people can consume. You double up the businesses that cater to these people you end up dividing the amount of money spent at each business.
This is one reason radio stations are going bankrupt in general. Years ago the cost to get into radio was expensive and basically a closed market. You had lets say 12 radio stations handling all the major advertising for a given area. Once the internet happened now you have access to dozens and dozens of "radio stations" to spend advertising dollars. The market wasn't all that bad but once something like SiriusXM "Radio" was available in cars that hurt the brick and mortar stations. Radio stations still had a locked market for drivers but then once they had access to SiriusXM that changed. My opinion.