It's a flawed strategy based on the imbalance in their personal relationship. It's a demonstration of power over her, not an investment strategy.
"I'm spending MY money on what I want."

The difficulty with hard asset investments, is that you can only sell them once. Most "investors" have little desire to be toting a high grade shotgun around at gun shows when they are 80 trying to pay for their prescriptions.
And even fewer follow an orderly liquidation of their accumulations prior to their death. So, the beneficiary is usually your "friends" with similar interests, as they are the ones that will see to it that your wife is properly screwed after your demise.

It's a lousy strategy. I know, I am there.

Out there doing it best I can.