I forgot to say.......
It could also be used for temporary sites; for example, a player-merchant who wants to open their shop up to the public during their on-line time, bbut close it off to the world during off-line time (casue' it'd REALLY suck to get base raped for doing good). since, bluntly put, npc merchants cheat, and pc merchants keep it fair, it seems only right that that's the way it would work.
also forgot to say.... it would be temporrary, as in "not permenant". it cou,d only be up, for, say, a half hour, then itd automatically be destroyed (and the player who left it would be sol to retreive it). anyone that shows up 'could' take it, removinv it from the map entirely, but npc's can't take them, so it would stay up until time expires or a player removes it.