Well, here's a problem: I think the story is intentionally ambiguous. By that I mean, some points made about race and racial prejudice are open and direct. These are easy to identify. Olaf's immediate reaction certainly sounds prejudiced; he sees a "huge black thing" in the doorway when the man enters. However, in the next page or so, it becomes clear that the hotel admits men of all races, and that Olaf has worked with the same array of colors. It is this man, and the combination of color and size—and then the dismissive fashion in which he spoke. He assumes Olaf will obey, and is casual about being much stronger than Olaf.
It then gets more complicated, because Olaf himself starts thinking about whether he is prejudiced or not; Lena points out that he's never hesitated before. Later, Olaf thinks the man will kill him, but not only does the man not hurt him, he brings him presents and calls him good.
If we had to sum up what point is made, it would be these points:
1) Prejudice can crop up even when you don't expect it.
2) Racial prejudice blends with other fears, like male concern over being tough enough.
3) Racial prejudice completely distorts how you see things. Olaf never did see clearly.