I'm not bothered by sexy game characters; games are entertainment, and attractive women are certainly entertaining. But what seems embarrassing and unprofessional is hiring lots of models to bounce around your trade conferences. You're there to work, the only people allowed are industry and press. And while you're at work you need to work with women who you should do your best not to creep out or demean.
I guess it could be argued that the booth babes are a form of advertizement, and there for the customers, not the attendees. But that doesn't really seem to be the case.