Though the idea in it selfs is good..

the world does not use bartering for practical reasons. so why should that be in the game?
you can already barter resources trough trades, that can only be done with active players. In all and every aspect, a bit logical that its not possible to do so with the AI.

some reasons why that would not be a good idea, nor feasible:
- the company would not be able to get money that way as resources will not be needed to ever be bought again with using gold, therefore the game would need to move to pure monthly subscriptions.
- AI economics need to be improved ni such a way that they would need to hire a dev just to go and do that, it would consume too much time
- the real world does not work on a barter system, though it would be great, imagine the logistical issues arising if it would
- i wanna be rich, have lots of monies. I dont want things, I just want monies :p