We need one of these at every Q&A:

I’ve stopped going to any panels at cons and such because of this. I hate audience Q&A and seriously run the risk of being the asshole in the crowd yelling to ask your damn question or sit your ass down because no one cares about what a big fan you are. We’re all big fans, that’s why we’re here.

It can’t possibly be that hard to have some sort of app that allows audience members to submit questions to the moderator, and the moderator can choose from there. This is the obvious solution.