The District is a small, and vibrant place. There are roughly 600K full-time residents. If it were a state, it would hold the title of 'highest population density.'
It's home to embassies from every part of the world and, you can find almost any kind of cuisine here from soul to Laotian to an Aussie style cafe to Mexican street tacos and everything in between.
The District's food culture is dominated by extremely high-end restaurants - steakhouses, Michelin-starred affare, James Beard Award Winners (and nominees) and the like, while also have a strong carry-out culture before carry-out became a thing. There is a lot of great food on either end of the spectrum, but not a lot of mid-priced places that aren't chains (even the chains are expensive.) The food scene is dominated by large restaurant groups (STARR, Clyde's, Popal, etc) and a lot of mom and pop style joints.
Layer in that DC residents spend 2-3x more than the average American on dining out and it all starts to make sense. This is a city where a lot business meals are expensed, and it's also a place where rapid gentrification over the last 25 years has drastically changed the city, and culinary landscape.
More on carry-out culture in the Mambo Sauce recipe post.
Sources
FOX Local
Christina Sturdivant Sani
Hero image from: https://guide.michelin.com/us/en/district-of-columbia/washington-dc/restaurants/bib-gourmand/1-star-michelin/2-stars-michelin