Why try to rank journals, even in this unsystematic way?

A senior philosopher with tenure expressed puzzlement (on Twitter, of course) about these rankings.  A junior philosopher responded:

For those of us whose professional futures depend on the snap judgments of people reading 100s of CVs, it is really important to have a rough idea of where people tend to rank different journals.

Amusingly, this senior philosopher was unaware that rankings are very common in many other disciplines, including economics, chemistry, political science, physics, etc.  Indeed, others have used the h-index to rank philosophy journals in the past.