In relative terms, that's probably like people on this forum buying a sterling silver ring; actually, just doing that probably represent a much larger investment in PM's than your story suggests the richest man in the world is doing.
If you want to know what the richest man in the world is thinking, then you'll have to look at where he is investing the other 99.999999999% of his wealth, not just one infintesimally small amount.
- pug