Yes but it's scarce. As he sells the price goes up so he controls the outcome. His nest egg permanently exists because it's limited, the supply will always drop. Selling the last dregs of helium for military contracts or private industry will eclipse any reasonable monetary requirements. He can hang on to the smallest amount for a long time.

If helium doesn't sell for that much at the last point then it wasn't worth that much anyway and he couldn't build a nest egg off a normal sale price.

I don't get it.