The DC Extended Uinverse in a way is following the same transition characters like Batman and Superman went through when they first debuted. When first introduced Superman and Batman were pretty dark heroes ( Batman the darker of the two) and both had killed like Superman with Zod or Batman with a good amount of criminals in BVS and it was only as time past that they started to get lighter similarly to how to Universe is suppose to get Lighter and Softer after Justice League. In a way The DCEU is following the comics they just aren't starting from the modern interpretations.
With the DC heroes possessing godlike power, it's no wonder their films tend to give them a godlike treatment:
Superman gets the Jesus parallel, with Man of Steel featuring Christian motifs and with Clark himself dying and being resurrected.
Batman goes the other way with his presence in Gotham being regarded as near demonic and with Bruce himself feeling he's stuck in hell and can't escape. He does get better though after encountering other heroes.
Lightning is considered a tool of godly power. Thus it is seen used by both heroic and villainous characters:
On the heroic side there are Wonder Woman (a goddess herself) and the Flash (as a Time Master), and the Shazam family (who inherited these powers).
On the villainous side there is Ares (a parallel to Diana herself as a descendant of Zeus), Doomsday (created as a bioweapon to rival Superman) and Dr Sivana (Shazam's rival). Steppenwolf uses an electro-axe which disperses electrical energy, though its power cannot reach those of true godly status like Superman and Darkseid.
The Suicide Squad has Harley reference this: she says rain feels like "angels splooging."