Nope, this guy has nothing to do with the campy HBO show about hawt vampires, fairies, were-panthers, and shape-shifters. Except, of course, that he shows up in a novel that basically interrogates what it means to be a less mythological shape-shifter. (We're blowing our own minds here.)
In any case, Trueblood isn't a bayou vampire. He's a poor, uneducated black man who lives on the outskirts of the narrator's college campus, Trueblood fits the negative black stereotype to a tee—and is amply rewarded for living up to it.
He's ashamed to admit he impregnated his daughter, but even more amazed at the whites' peoples behavior towards him afterwards. They give him food, tobacco, and money. Which: what? How on earth does this make even the smallest bit of sense?
Well, we might think of this as the dominant society as rewarding the types of behavior that coincide with white ideas of black manhood. Black men who adhere to certain constructs are celebrated and held up as an ideal. For his lack of education, poverty, and incest, Trueblood embodies one such negative stereotype of black manhood and is, ironically, given presents because of his behavior. We can think of Dr. Bledsoe in similar terms, since he also benefits from adhering to white notions of black manhood (in his case, of what an upstanding black man should look like).