I don't go because I have limits on how much I allow myself to geek out.
I go to Anime North every year for the past...I don't know 5yrs? Its the 4th largest con in N. America. I mainly go to cons to buy stuff, since there are no tax and you can haggle. Course there are events I attend to like the masquerades and the amv contest.
I wouldn't want to go to the ones in Japan, even I have limits. Although parts of me want to.
It is kind of interesting to see the reactions here. It seems that there are a lot of high school aged and younger people on this forum, and that parental consent is a problem. I guess that's just surprising since I've been on this forum since I was at that age.
Oh man, I feel old.