I remember 6-inch Italian hoagies being sold for fundraisers back in the 60s and 70s—locals would buy them to support schools, firefighters, and other community causes in South Jersey. (Heck, they might still be doing it.) They made a nice snack.
I’m thinking high traffic and also that limited hours means a limit on the payroll.
I don’t know that area - but there are areas where there isn’t any business after lunch. For example, there is an area not too far from me where restaurants etc., are open M-F until 2:30 ish . Because all that’s there are some government office building and courthouses. No stores, no mall, not a residential area - so they really don’t have any business after the court lunch break ends at 2 pm.