So would you expect to be charged to enter a Transair Shop, or a visit to Harry Mendleson's place in Edinburgh?
It's a ridiculous concept and, given the moans and groans on this forum about being charged for everything else I can't believe that anyone would support the idea of being charged to enter what is no more than a big shop.
Boycot any trade fair which charges you to enter, then the industry will get the idea.