Adam Shepard is white - I know this from his picture on the cover of Scratch Beginnings. Some of the people he lives with in the shelter and works with at the moving company in Charleston, SC, are black. I think. There are clues in the biographies and dialogues he gives us that suggest as much. So does the sheer demography of Charleston. If there is a hero in the book, it is Derrick, the best mover in the company who becomes Shepard's partner and landlord. Several context clues suggest strongly that Derrick is black.
Yet it is a remarkable fact about this book and the world it illuminates that race never intrudes in the story. The men in the shelter and on the several jobs Shepard has seem to be of many hues and ethnicities, but that is not central to their story. And it is not possible that a college-educated Southern white boy did not notice race or did not think about whether it matters. My guess is that Shepard was determined not to make race one of his standards for measuring people. When he was writing his story, his race did not seem to be central to how others were measuring him. I believe he must have made a conscious decision not to tell readers the race of the people he met because it was not really important to the story he was telling.
I take this as a measure of progress. Adam Shepard is of a new generation. Survey research suggests that Millennials think that ethnic variety is a good thing, and race just doesn't tell you much about what another person is like. If this means the rising generation is less obsessed with race than the retiring generation has been, then we are indeed making progress.