They could establish a gulag there and ship prisoners to it. Then have them grow wheat to be sent back to earth. And have a warden run the whole thing with the aid of a sentient computer named 'Mycroft'.
Riiight! And lasers can whistle!
what would constitute "proof", Sparky?
Retroreflection is accomplished by having three mutually perpendicular reflective surfaces forming a hollow corner. Natural cubic crystal formations can easily develop hollow corner retroreflectivity. So, to show that it was the Apollo lunar ranging experiment, and not a natural crystal formation, you'd at least have to have before and after shots showing the difference.
So you think that money is the root of all evil. Have you ever asked what is the root of money? -- Ayn Rand