you need to have a lot of aircrafts and sacrifice a lot of game-time for travel to have real advantage from this mechanic. It is exploit but not really fun to… exploit.
I admit that was my initial reaction too when I first discovered this.
However, after experimented more with trading, I would say, no, it is not game breaking, largely because it takes time to replenish the stores and existence of efficient trade routes depends on RNG and protecting havens.