You'd guess so, but this has already been in the game for almost a year (maybe has?) as you can see from this vid that also got 50k views. I think the one thing about this exploit is that it's a bit more complicated so most players just can't do it so it doesn't spread around as much as easier exploits.
I think the price should be even more different to get better deal in villages. Trade (honest) is too petty in it's skill gain compared to how much campaign time is wasted tacking goods from one location to another. I also think having caravans use the players trade as an option would be good and help trading actually fit into the rest of the game. As is, it's completely asinine to think the player would continue trading after making even slight progress in the game. Using caravans as your proxy would solve this.