That's about the norm around here too. I draw the line at $5 and/or 5 gallons of gas. As I understand it, the reason for charging a token admission is to guarantee to dealers that the only people who visit their tables are those who are serious customers. Hence the wording of that flier. A few bucks admission keeps total bums from wandering in, but I don't think that earns any serious money for the show organizers.