To the OP: DEMA is a wholesale trade show requiring a buyer's license to transact business directly with the manufacturers. Confidential wholesale price lists are floating around and dive shops and manufacturers really don't want the diving public to know what those margins are. Industry folks (dive shops, resort shops, etc...) come in from all over the world and most of the manufacturers get fully booked with appointments before the show ever starts. I've been a non-voting member of DEMA for decades and acted as both buyer's and seller's agent over the years. Since it is an industry trade show, instructors (including independent instructors) are considered "industry" but still have to go through a remarkably detailed vetting process. I don't know if assistant instructors or divemasters are included as well (I seem to recall they may have been at one time but haven't kept up on that aspect for a while). Even with only "industry" folk present, the aisles are usually pretty crowded. It takes me an entire day just to walk around the show once - those convention center venues are huge. If I stop for any length of time to talk with old (and new) friends, it can take me two days to walk the entire floor. Throw in attending some of the seminars and clinics and you have used up three days easy. For a couple of the Las Vegas shows I've flown out from So. Cal in the morning, taken a Uber to the Convention Center, made a bee-line for the booth or booths I have an appointment with, do my business and fly home that same day (hopefully with 10% commission on a $250,000 order in my pocket.
DEMA is a great experience and I wish everyone could find a way to experience it at least once. It is a working show however and really nothing like the big retail shows (save for the booths and aisles of course). My 2psi.