Justice League Easter eggs!
Not only do the various items in the room with the two boys highlight how tightly wound Shazam is in the universe, it also makes clear that one of the prevalent themes of Batman v Superman - that superheroes are mistrusted symbols of controversy - has now been reversed post-Justice League. Shazam shows the heroes of the DCEU are idolized, especially by kids.
Related: The DCEU Is Finally Generating Good Post-Justice League Buzz
Going left to right across the image, here's what kind of swag is in the room with Billy (left) and Freddie (right):
On the shelf above Billy's head is a Superman baseball cap. This headgear is reminiscent of the T-shirts and other Superman merch for sale on the street that Amanda Waller walked by at the beginning of Suicide Squad, which took place in the time period soon after the Man of Steel's death.
Next to the cap on the shelf, in front of a collection of graphic novels, is a Batman action figure. Judging by the blue and grey costume the doll is wearing, this is a mock-up of his usual Batsuit first seen in Batman v Superman.
At the rear of the desk beneath the shelf is a Superman travel mug.
Next to that is one of the coolest things Freddy owns, a Time magazine with a photo of the Kryptonian World Engine floating above the ruins of Metropolis as seen in Man of Steel. The cover story - "An Act of War!" - details the Kryptonian invasion, a.k.a. the Black Zero event, which happened in 2013 (Billy and Freddie were about 7 or 8 years old then).
A patch of Superman's "S" shield logo lies in front of the magazine while another Superman cup or pencil holder is next to the issue of Time.
In front of the Superman mech on the desk is a Batarang on its base (presumably a replica and not a real one like Barry Allen kept from Bruce Wayne in Justice League). There are also more unidentified books or graphic novels on the desk.
As Billy looks on in the foreground, Freddy, who is wearing a black Aquaman logo T-shirt, holds up a plastic baggie containing a smashed bullet shell and a Certificate of Authenticity. This could be an authentic bullet that was once fired at Superman and bounced off his impenetrable skin (could this also mean Billy or Freddy is one of the kids who met Superman in Justice League's worst scene?).
Finally, on the wall on the right, hangs a copy of the Daily Planet with the headline "Superman Is Back!" This confirms Shazam definitely takes place after the events of Justice League.
Related: Shazam Movie: Every Update You Need To Know
What's more, going by the sheer amount and variety of merch, the superheroes who saved the world from Steppenwolf are now extremely popular. Perhaps the League has even already constructed the Hall of Justice from the ruins of Wayne Manor.
If anything, Freddie's collection shows that in Shazam, the superheroes in the DCEU are now what they are always meant to be: protectors of Mankind who are also inspirations to everyone, especially children. And this includes Billy Batson himself, who will utter a magic word and soon take his place among those mythic heroes.
