If true, there is probably something in that choice that remains in human nature from earlier animal forms. Ripe fruit versus unripe fruit? Is our brain set to react in excited fashion to bright colors in food selection? Is that why candies are often bright shades? Humans might sneer at dumb animals, but we are not that far removed from them.
Identical buttons doing identical functions. The only difference is the color. Yet it made a difference to people. To someone as logical as Dilbert this makes no sense. So he's giving up trying to figure out human intelligence, again. This is typical of the projects and the results they generate at his workplace.