[dannyw]

And three sentences of "We don't tolerate abuse, discrimination, or harassment of any speaker or participant at XYZCon. If you have a problem, contact a staff member. If you cause a problem, you may be asked to leave, be banned from future events, and/or the police may be called.

[RonanTheGrey]

Exactly. In generations past this was called "respecting boundaries" and was something we do as a social activity -- we literally teach others how we are willing to be treated (or more generally, we teach others what behavior will be accepted in that social group).

Despite the increasing anonymity of the world (in that we don't physically live and interact in the same physical space), I think conferences are still small enough social groups that such approaches do work. I've been to some where despite the presence of thousands of people, noteworthy news takes less than a few minutes to travel throughout the conference.