[nhaehnle]

I'm pretty sure that only a minority of rich people are really in the ideas and creation business. If you live in Silicon Valley it might appear different, but globally speaking, the rich tend to fall into the categories of (a) inherited wealth, (b) upper management, (c) non-hard-science knowledge worker types (finance and lawyers).

Yes, r > g is only an aspect for (a), but the Piketty argument also has to be understood as a warning bell. After all, wealth and the resulting political influence make it easier to ensure that mostly (a)-types ever get into (b)- and (c)-positions in the first place. (And the tendency for this has always existed and exists today, just look at the university system in most countries for evidence.)