Generally speaking, just because there's a film based conference doesn't mean we all have to attend it to support film based photography. Especially if the event is poorly run by a crook. I can recall such an event.
Then I am sure a crook won't bother next year. Particularly if it affects his or her sales, and not film photography in general.
Let me ask you something. If the rule you followed brought you to this, of what use was the rule?