Yeah, Shazam is a kid hero whose adult alter ego means he can hang out with the Justice League rather than the Teen Titans. Note that before Flashpoint, Freddy didn't become an adult when he transformed, and as CM3, then-recently renamed from Captain Marvel Junior, he was a Teen Titan (Billy didn't ever join the Titans, and associating with them in Academy only resulted in his identity being compromised). Whereas Billy once joined the Justice Society, and got told off by Jay Garrick for trying to get close to Stargirl - when in reality, they were the same age. Jay didn't know that of course, he just saw the adult Captain Marvel messing with a teenager.