An unstated, but obvious, reason is that much of that was not properly taxed.... or, worse yet, simply stolen (in one way or another).

But, whatever the source, a cottage industry has developed during the course of the past several years... help them get long term visas (which convert into green cards), and make it easier for their kids to attend Harvard --> nice value proposition for, otherwise boring, investment products.

By in large, the bulk of them spend most of their time in China (where they can continue to amass wealth), but they "live" in Palo Alto.