In pretty much any group big enough, there's always that one person who kind of belongs but who also kind of doesn't. This is one of those times, and Antoine Christophe—otherwise known as "Dirty Red"—is that person. Just check out the way that Cherry talks about him once the gang's assembled in the cemetery on the way over to Mathu's: "We had never mixed too well with his people," Cherry tells us, "We thought they was too trifling, never doing anything for themself" (6.22). Just a little while later, as if we didn't already get the point, Cherry lets us know pretty directly that Dirty isn't one for work of any kind. "Even to bat his eyes was too much work for Dirty Red," Cherry says (6.25).
It's important to remember that what Gaines is doing here is more than just making sure we get that Dirty is an outsider. He and his family have been treated like outsiders for so long because they don't seem to want to work. Gaines is telling us that, at least in this small, Southern Black community, working and the quality of work you do says a whole lot about you, and does a lot to affect how people think of you.
Dirty Red might have a reputation as a lazy, good-for-nothing, no-account loafer, but taking a stand at Mathu's is going to change all that for him. Just take a look at what goes down when Mapes tries bagging on Dirty Red:
"Shut up," Mapes said. "You and nobody in your family ever done a thing in this world but worked hard to avoid work."
"Till today," Dirty Red said. He looked up at Mapes, with his head cocked a little to one side to keep the smoke out his eyes. "Today I—"
"You trying to cut in on me when I'm talking to you?" Mapes asked him.
"Look like he's doing more than just trying," Johnny Paul said, from the other side of Mapes. (9.55-8)
Dirty Red might not be saying a whole lot in the passage we cite above—and some other characters might say that's just how lazy he is—but Dirty Red stands up to Mapes here. He implies that he's sick of not getting any respect from anybody. Red may be kind of an outsider, but he's the last one to talk to Charlie before the guy dies, and Gaines wants us to understand that something as simple as standing up for yourself once can do a whole lot to change a person for the better.