It does bring a question up about the idle rich though. Perhaps this generation won't be that way, but pretty soon, what happens when wealthy people are mostly happy to sit on their laurels.
If Bill Gates' kid takes the $105 billion, Bill G gives em and just puts the 5 billion in petty cash, grows the rest at 5% compound interest, in 100 years, that is $13 trillion dollars. No risk taking, just banks using that money for loans that hopefully pay off. Sure in 100 years 13 trillion won't be what it is now. But even estimating 2.5% annual inflation.. the real value of that money would be 10 times greater than now, just for doing absolutely nothing.