In all honesty, you should take 'E3' and replace it with 'everywhere'.
I was at a conference last week, wasn't E3 or WWDC. We hired 'Booth Ambassadors'. They were dressed fairly conservative, but had tanktops on under a light jacket. This was a computer industry conference...
I'm a big fat older nerd. However, at one point, I almost turned around and decked a guy for what he said to one of our two ladies working with us. They were professional, not meant to be alluring in anyway sexual, yet the innuendo, stupidity and what not I heard from men OF ALL AGES, even greyhaired old farts.
During a quiet point, I asked one of the ladies about the comments and asked her if 'Nerd conferences' were worse than 'regular things' and she said 'Quite honestly, and no offense, it's Men in general'.
She felt it came with the territory, but still....unacceptable.
(yes, i have three little girls, so it bothers me a lot especially since my oldest has started sending me links to Cosplay stuff saying I WANT THIS FOR HALLOWEEN)...i'm doomed.