I can't speak for vendors and the price they pay for table space, but I don't think 20 bucks is unreasonable for what is offered to the public. Compare it to a movie ticket,concert ticket,dinner,or a few good micro brewed beers and price doesn't seem to bad. If newby is just getting into doubles ,I think the guns and prices he sees once in the tents will probably scare him alot more than the $20.00 entrance fee.
Just my thoughts, Dave