Sure, it's fun to see stuff in person, but the logistics for sellers and buyers is ridiculous. You have to pack everything up, maybe rent a truck, travel hundreds of miles, stay in hotels, spend thousands of dollars on a gamble that you will sell the stuff you brought along. For many, it's a tradeoff, you "give away" stuff just to break even with expenses. Then you have to lug the stuff that didn't sell back home. There could be an offshoot business for some people who have time to do pick ups and deliveries or professional packing...
Sellers could have individual pages that they would purchase in lieu of actual "tables" or spaces to list and picture their stuff (photographed by capable photographers) and no additional buyers premiums or seller fees. Potential buyers would have to pay an "admission" fee to log into the site, which would be accessed by password from a single specific computer or device registered to the buyer. The access fee would be more on the first day or could be one price for the entire event. It could be done several times a year with no problem. This would mean that no one in the hobby would have to miss any of the shows because of distance, schedules, expenses, etc. - you could buy stuff from the privacy of your room in the nursing home...


It would not be an online auction, all sellers would have to list their prices and post them with the items... no sellers soliciting "offers" without prices. Of course, sellers could negotiate with a potential buyer on lowering the final prices. This would also eliminate some of the problems of getting buyers who have money to spend, to the event without having to waste time and money on travel, etc. Even thought the collecting community is small, there are a lot of serious collectors who have never attended a show because of time constraints, etc.
Individual groups could also have supplemental get togethers during the year to accommodate those collectors whose main interest is social...