[cafard]

One could do a certain amount of that credibly. Oxford World Classics consistently uses white spines with red lettering; Penguin has a couple of different styles; Oxford's Greek texts are in blue dust jackets, its Latin texts in green (I think). On the other hand, Dover will print one author's work, sometimes the volumes of the same book, in different colors (Spinoza, Schopenhauer, Doughty).

If one wished to cultivate a reputation for eccentricity, one could have the first volume of The World as Will and Representation shelved with the greens and the second volume with the reds. Of course, both volumes would have to show evidence of reading, or the tactic would fail and leave one with with pseuds.