This is a valid point, admittedly. Maybe we could allow people to view the stuff being sold even if the person isn't in the zone, just as long as they are online? All you'd need to do that way is actually meet the person to make the trade, if you don't want to hang around the zone.
There would be an advantage and a use for the trade zone, and people could easily hang around there if they like the EC style marketing, but it wouldn't be necessary.
Say, something like a halfdozen "lister" npcs, you talk to one and it stores records/links of the items you're selling for X hours, and people can any of the NPCs (there would be several just to prevent a single NPC from being mobbed

) what you're selling, then contact you if they want to buy one of the items you're listing.