It's mostly about homeless people, actually. Homeless folks eat almost exclusively fast food in places without soup kitchens because you can panhandle enough to scrape up 3 dollars and get a mcdonalds cheese burger, fries and a drink. If you don't have a kitchen, don't have anywhere to stash canned goods, etc, the most appealing option becomes dollar menus at fast food places, especially when those places also have locking bathrooms in which you can shit, clean up, or do drugs.
A lot of people in deep poverty will also eat off dollar menus during periods where their power is cut off and they can't cook, but more often they stock up on things like canned greens and fish, peanut butter and bread, etc and go out for the dollar menu when the constant sameness starts to make them sick (which it can do).
Stephanie, however, isn't in deep poverty or any kind of poverty. She's broken the allotment down into a daily limit instead of a weekly limit. At a weekly limit, its hovering at around 50 dollars, which, spent purely on food and nothing else, can definitely purchase one meal for every day of the week. You won't be eating calamari and ice cream 4x daily on this budget, but you wont starve to death.
