Couldn't you dress up and hang outside the convention center and pose for photos?
I imagine that would be similar to the characters who hang out in front the the Chinese Theater in Hollywood.
I wonder if a TER Comic-Con gathering would be possible. A bunch of folks dress up, meet at a designated spot and "crash" the convention. 
Hi!
There's no such thing as "tickets" for SDCC (San Diego Comic-Con) anymore.
They're now called Badges (or Passes).
The only reason for having a Badge/Pass is to gain access for all of the panels at the Convention Center.
Also, Badge/Pass holders can enjoy the Main Exhibit Hall.
There are usually cool things to see in there, as well as art and other (exclusive) stuff to purchase!
But, that's only 10-20% of the fun.
Even if you don't have a Badge/Pass, you can still have tons of fun during SDCC!
All you have to do is trolley to Petco Park! There's a Carvinal-style FunZone there!
On top of that, there's even more fun stuff to check out and do at the nearby hotels and all over the Gaslamp Quarter!
Best part?
All of that is FREE!
And not to mention all of the great restaurants, pubs, bars and other dining establishments there!
And, just because you don't have a Badge/Pass to get into the building, that shouldn't prevent you from cosplaying as your favorite pop culture heroes!
You'd be surprised by the hundreds, if not thousands!, of cosplayers that are roaming around the Gaslamp!
Now, I know that all of this info is either REALLY LATE or Way Too Early!
Hopefully, this will help you encourage y'all and help y'all plan for 2024's week-long event next summer! 