Because without an easy way to advertise and trade items it would destroy the game.
Maybe they could think about introducing some kind of auction house?
I really feel bad for everyone here. I feel bad for the developers because it must be hard to admit that your creation just didn't quite live to everyone's expectations. And I also feel bad for the Diablo fans because you could really see how excited they all were for this title.
At the same time, I admire the fact they admitted it wasn't exactly what they had in mind. Most developers would go "Oh, it's the audience's fault" or "Figures they wouldn't like it if its not CoD". So props for that?
Can you imagine EA admitting something was wrong?
I actually thought the AH was a decent idea, until I read that real money came into play.
For anyone who played D2 online you'd know that gold was completely worthless, and the only things worth anything were runes, gems and very powerful set items or weapons, everything else may as well have been garbage. You could not trade for anything useful unless you were a level 99 god who could farm hell mode.
The AH tried to make gold important again, making it worth having.
The real money thing was absolutely retarded though.