I suppose by having the event at Epcot, instead of DHS, you remove the speculation that you "might" get early access into the new star wars land.
Another part of me also thinks this event has to be planned in advance....and maybe they hoped to give a dvc preview to these folks, but with earlier opening that altered things.
Though I wouldn't be surprised if there is some sort of star wars land related announcement at the event, as you have to assume a huge part of your target audience will be attendance.
......just announced for DVC members, get your exclusive access and early reservation to the new star wars resort. Only $2599/night double occupancy, includes darth vader cupcake.
In all seriousness, you'd have a valuable group of people together to gauge certain ideas.