In fact it does, there is WonderCon and APE or Alternative Press Expo. They're held at Anaheim and San Francisco respectively.
Yes it is pretty expensive, and its a four-day event (Thursday–Sunday) held during the summer, so staying there also makes it more expensive
I would like to go to the San Diego comic con one day.  have you ever been? I have not, although I understand its a multi-genre entertainment and also comic convention. I have seen on the internet that people dress up as their favorite characters.  Would i be out of place if i dressed up like Mr. Pickles, the dog from the cartoon network? I'm not sure of the approved outfits for it but if you manage to go, there is a pre-event called "Preview Night" that happens on Wednesday evening. I guess I'll have to see if I get lucky. Does Comic-Con have any other conventions?
Comic-Con International also produces two other conventions, WonderCon, held in Anaheim, and the Alternative Press Expo (APE), held in San Francisco.