There actually is a logical reason for being careful about moon mining. The Moon is currently thought to be the reason Earth is habitable, by gravitational force. It causes the Earth's core to rotate within the planet, keeping the iron core molten. This rotational effect is what generates the Earth's magnetic field and keeps the solar winds from stripping off the atmosphere. Anyway, reducing the Moon's mass will lower its effect on Earth by both reducing its gravitational oull and causing it to spin away even faster than it already is. Currently the moon is moving about 3cm away from Earth each year. Less mass, same speed, this will increase until it's far enough away that it breaks away, then we're screwed.
Initially it won't be a problem but smart humans will only take enough out of the Moon to get a mining base waystation set up, then will devise a way to bring safely asteroids to the moon for processing. Careful monitoring of the Moon's orbit after that will let us add or remove mass (over time) to keep the Moon a stable distance from Earth.
If nothing is done, life on Earth will be gone long before the Sun envelopes us, it'll be gone shortly after the Moon disappears on us.
https://www.physicsforums.com/threads/will-the-moon-escape-earths-orbit-in-billions-of-years.364921/ Or, maybe not. It'll be something for future boffins to worry about.
Biting the hand that feeds IT
