Why are there so few cheap restaurants in Anacostia?

I had lunch there lately, in the new and excellent Ray's the Steaks, East River edition (superb chili, fried chicken, mac and cheese; recommended).  Yet I drove around the general area for about forty minutes and hardly saw any other restaurants to speak of.  The five or six other times I've been to Anacostia I had similar impressions, even more than in other "ghetto" areas I have visited.  

What might be possible explanations?

1. Poverty: Yet there are other retail establishments and per capita income there is surely not so low.  Plenty of poor countries have plenty of restaurants.

2. Risk and crime: Yet you will see other cash-intensive retail businesses in Anacostia.  Is it so hard to hire a guard?

3. Traffic: It is easy to get in and out of Anacostia, so perhaps residents drive to eat out elsewhere.

4. Diversity:  Perhaps it is the demand for different kinds of food which increases the number of restaurants; yet Anacostia is not so ethnically diverse, as it is heavily African-American.

5. Labor supply: Cheap restaurants rely on low-wage laborers who do not have cars, and it is actually fairly hard to get to, and get around, Anacostia.

6. Proximity to business lunch demand.  Not so much.

7. Fast food: You will find McDonald's and Subway in Anacostia.  Since they serve high volumes, maybe that lowers the total number of restaurants needed.  This is related to #4.

8. Foot traffic: Not so much, although the suburbs deal with this problem just fine.

What do you think are the major factors?  What have I failed to list?

In the 12:30 to 2 lunch slot, the Ray's across the Anacostia river was never more than half full, though a Ray's elsewhere will be quite crowded during those hours.  In all fairness, this Ray's has not been around for long.

I thank Ross Douthat for a useful conversation on this topic.