Talking too much about that difference would spoil the story, but here readers are introduced to the setting:
“There were three quarters on the wood indicating that three challengers still remained. And he looked then at the soft, velvet green of the table itself, that held him, he thought, like a lotus land, and finally to the blackness of the eight-ball and the whiteness of the cue, good and evil he thought, paradoxically flowering here on the greenness of this plain.”
The language in the opening paragraphs spirals around sin and redemption: “forever lost”, “desperate hope”, “condemn”, “righteousness”, “awakening”, “saved”, “doomed”, and “underworld”. So, this description of the pool table with the contrast of eight-ball and cue paralleled to “good” and “evil” is fitting.
How Jesse experiences the events of this evening, and the morning that follows, is viewed within this prism, in a landscape of black and white—but also green. And it’s the “greenness of this plain” which introduces a third colour, something that Jesse struggles to place on the palette.
But the title talks of ‘green’ and not ‘grey’ and that’s because how the story ends is not as you might have guessed. MacLeod even seems to phrase the resolution is such a way that readers can slip past a single noun, one which clarifies a transaction that we might have viewed another way, if we so chose.