Sorry, but that is exactly what I am trying to say.

As CD, (or "event director") his RESPONSIBILITY is to the attendees and to the AMA for doing the job he signed up for.

He does have to be there for the entire time.

If they are so irresponsible that they would leave the event after a minute or an hour, they do not deserve to hold the title of "CD".

That's my opinion, not AMA's, but AMA probably thinks along the same lines.