Earlier quoted context omitted.
The problem with differentiating between the "good investor" and the "lavish lifestyle guy" is that the good investor is actually the one that you (rather, Piketty) need to be most worried about. People worried about inequality aren't (just) worried about the morality of consumption -- a fat cat sitting atop a mountain of cash drinking champagne and eating caviar while the peasants starve. They're worried about maint…
What about the common libertarian viewpoint that we should limit the scope of government so that the rich guys don't have any significant political power to hijack? This comes without the slowing of economic growth that would be caused by higher taxes on capital.
They're all in it for themselves. The key is to ensure that there isn't a big enough state to corrupt so they can consolidate and entrench their power.
A small state prevents monoloploies from being formed and from using those wielding power to consolidate their power. And then it doesn't matter how evil the guy who gets the top job is, because he just can't make a big difference.
At the heart of all this is how England managed to keep its Anglo-Saxon self-government traditions even after the continental Norman invasion and takeover. Because the Normans could only ever wield limited power at the state level, they could never fundamentally change the way the content was run at a local level. So citizen assemblies and English common law continued and was never replaced with continental law, the final iteration of which is based on napoleanic code. Thus in England, and her spun-off colonies, you're fundamentally free to do your own thing unless there is a specific law against it, while most other places state that you can only do something if there law explicitly states it.
This fantastic inheritance was all bequeathed to the citizens of those countries with legal systems based on common law precisely because England had a weak central government which reduced the ability of a king to control everyone, especially when that was a foreign king who had invaded.