Well, yes, that is one caveat—any water that is shipped off the moon will be lost, but keep in mind, we will probably be bringing in more than we take. People coming to work on the moon won’t need to take any home if they return to earth, but they will probably bring some with them, in the form of bodily fluids, food and bottled water. The only ones taking water will be missions to Mars that leave from the Moon. I think the Moon gains water in that equation.