Dammit. I can think of a word for each letter of SHAZAM that isn't comic book or AFi appropriate! Lego is really putting the screws to a good percentage of their fanbase with stunts like this. Exclusivity may trump availability, but these are Lego Minifigures. And these convention exclusives are purposely made in extremely small amounts for no reason other than 'Hey, look at this fanboys!' Or, 'Hey! SDCC-goers! Pad your pockets with this when you sell 'em.'
On another note, if anyone actually manages to snag these Captain Marvel(or other Lego promos) at SDCC this year, keep those of us who cannot attend in mind. MYXLPLYX would be first in line for such a request. I humbly add myself to the list in second place.
A list? That's a good idea. Check out the main Brick Builders section momentarily