The need has already been disclosed. A billion dollars is needed to live a billion dollar lifestyle. The definition doesn't limit a person to someone else's standard of what qualifies as a "need".
The definition operates within the scope of a given scenario with a set of objectives: To do this, you need this.
That setup doesn't encompass any prerogative-based antecedents--and there's nothing within the definition that states it must extend that far.
Frankly, the last 20 posts are so abstract and unrelatable to anything that I'm rapidly losing interest.
In an effort to tie it to something tangible, I was just watching John Stossel, and he questions whether self-interest or charity is more generous.
So attempting to tie that to a hypothetical billionaire's lifestyle, a billionaire acting in his self interest creates more jobs and benefit to more people (such as John D Rockefeller creating the oil industry, to replace the whaling and whale oil industry, paving the way for internal combustion engines and cheap feul, and inexpensive cars. Or Bill Gates creating an easily navigable computer operating system that basically lowered the cost of everything for billions of people worldwide)
As opposed to a billionaire who gives away the same money to less well-administered use of those resources (i.e., they hose it away inefficiently and create less benefit with that capital, to less people).