East only draws this crowd because of the huge proximal population. If PAX East moved outside of the New York/Boston/DC megalopolis, attendance would drop by over half overnight.
MAGFest would lose probably most of its current attendees if it went to Vegas: they can’t afford to fly there.
Most cons draw mostly local attendees who can’t actually afford to travel. That’s why if you go to any larger con outside of the biggest population centers, it’s 90% locals who don’t ever go to other cons.
PAX West, Dragoncon, SDCC, NYCC might literally be the only exceptions in terms of drawing a truly global audience.
The mega convention centers truly suck from an attendee perspective, and NONE of them are proximal to the big nerd populations. And frankly, if the Vegas con infrastructure were somehow transported to the Northeast, I posit it STILL would not be enough. I believe strongly that without physical limitations PAX East would sell 150k+ badges.