Lets face it, near impossible to get the main traders under the one roof. Too much shit has transgressed.
Some Pinball traders need to employ public relations employees, a staff member that can offer a fresh welcoming face/be the mouth-piece for the business. Such staffers could attend the expos, and make it possible for competing companies to be under the same roof, for the good of their business, and for the good of the hobby.
Sounds simple, because it is a simple solution.