Food is featured a LOT in the series. But the only people you see eating home cooked meals/dinner table meals are law enforcement/lawyers/9-5 types. The drug dealers, fiends, and corner kids are shown eating a lot, but it's always takeout or junk food from the corner store. The exceptions are when they are invited to eat at a proper table by people not in the game, like Naymond when staying with Colvin or Bubbles when he is brought upstairs to have dinner with his sister or Stringer when he goes to have dinner with Donnette (which happens while he is trying to go legit.)
There is also the time Avon prepares ribs at a cookout type event, which makes sense because the Barksdales are a strong family, at least on the surface, so having dinner together and meeting the baby moms and children helps to reinforce their foundation and at least present the facade that they are united like a normal family.
Randy's foster mom makes home cooked meals and offers Carver some, again showing she is on the straight and narrow, but the one time we see Michael try to make a home cooked meal for his brother, you find out his mom sold the rice-a-roni for drugs. The one time we see Bubbles making hot dogs for dinner is when he is trying to make a home for Sherrod.
Home cooked meals at the dinner table is used in the series as a symbol of home stability and represents the American dream of living a normal, healthy, successful life. Herc finally feels like he has "made it" when he gets invited over for dinner by Levy to have his wife's brisket.
