I would agree that 'in the world of Eberron' that is what is supposed to happen, and if this was a novel series then absolutely the protagonists would have no problem doing so, talking and working with everyone and anyone. But I'm saying as a practical matter at the game table... I personally do not believe most players do that. They've been conditioned not to by DMs always trying to take them by surprise. DMs LOVE to take their players by surprise because it's one of the few ways the game gives the DM the advantage, since the actual game rules are designed to have the PCs succeed most of the time. I mean, isn't that why we have all the complaints about Darkvision? Because Darkvision removes one of the better ways DMs have of surprising their players, and if that happens, what's left? Well... the only thing that's left is for narrative twists in the story by having supposedly-friendly NPCs sudden turn on the party and force their will upon them (if not outright try to kill them.) And players know this because they've experienced these DMs trying to do it to them. And that's why (I believe) they usually will not give any NPC anything and just do everything themselves as they play the game.