Sure it has the "Big 3" plastered on the front, who happen to also share screen time in the movie but plenty of their team mates also show up to tell you the good news about this year's most exciting breakfast treat:
And the entire roster shows up on the back of the box doing their patented "Justice League Lineup Pose" including some First Appearance info, and of course secret identity info:
If you want to get technical, then sure, Catwoman was technically a part of the Justice League line up during the Grant Morrison years but I've never bought into the idea of Robin being in the League. Sure, maybe Batman let him tag along to one or two of the meetings but he never got his membership card.
To put this into a historical perspective (which I know you were begging for), superheroes are no stranger to the toaster pastry genre. Back in the Spider-Man movie heyday we got two different versions: