Apparently, some people at DC Comics are still resisting the Anti-Life Equations. To appreciate this, you may need to be a certain kind of comic book geek.
FWIW: You may recognize the high school janitor in this TT excerpt as Darkseid, who had a one-day gig as the school principal in a previous issue.
The green lantern scarcity and "Blackest Night" refer to a too-wretched-for-words current DC story arc, in which all currently-dead DC superheros come back from the grave as flesh-eating zombies. (No, really.)