If you have capital there is no need for productivity, you are one of the protected parasite capitalist class. God bless USA.
There are two types of rich people:
1. Inheritors
2. Those who know how to not spend money.
Gee, lets take a case study for that. Let's pick up... hmm, Larry Ellison!
Let's see if he fits all your criteria:
* Parasitic capitalist class with no productivity - Well not really, having founded Oracle and made it a cornerstone for a way businesses work. Even communist sweatshops have production management done on SQL.
* Inheritor - no, actually he came from a pretty modest background.
* Not spending money - well the guy runs yacht races, has a business jet and donates tens of millions of dollars.
100k isn't anywhere CLOSE to being rich. It's middle class. 500k/year buys you lots of freedom but you're still not rich.
Luxury goods companies target what they call "UHNWI", or Ultra High Net Worth Individuals. These are the guys that have upwards of $30m.
This is "rich". I don't think it's fair to tax the guy who makes $500k/year as a working, independent contractor just like you'd tax one of these guys.
Basically, you can't tax the rich. You can't do it because at a certain level they begin acting like mini-corporates, with accountants and assets management companies and trustees, which is not done just for taxation purposes but for other, legitimate reasons as well. Taxing them would severely affect the economical activities of business entities in a way that won't do much good for the economy.
You can go after the little guys, the ones still working as regular, but well-paid, employees or contractors. But there's not much social justice in that, and I'm not sure there's so much money either.