People want to associate themselves with things that they consider cool. Hence, the existence of celebrity and athletic endorsements. It’s coolness by association; you may never be as brilliant as Einstein, but you must be KIND of brilliant, if you share similar tastes, right?
So people create personas of themselves that they imagine work like this:
It’s never, “Brad, my sociopathic colleague likes his coffee the same way I do…this must indicate some deeper commonality between Brad’s innate self and mine.”