The fact that they were completly bald tells me the wear is even, albeit evenly terrible. Any chance that the tires are rubbing on the wheel well? If it were a ball joint problem, you would have cupping. If it were an inflation issue the center would be worn (over-inflated) or worn on both sides (Under-inflated). If the tires are worn on one side, the usual cause is camber problems. These would be the main reasons for rear tire wear. On the front, you would have additional issues.

If you rule out the above, I would go back to the manufacturer and tell them what happened. They could very well be defective tires.