In your original comment, it sounded like you would encourage billionaires to buy yachts, solely "for the good of the economy".

Scenario D: A homeowner adds 10 window to their home because the populous think he is stingy and will send him to the guillotine if he does not start spending his money on new windows!

Scenario D provides no benefit to society.

If the billionaire does want the yacht, then no encouragement is needed.