Creating value and receiving some percent of that as rent is not inherently a bad behavior. But if you think you have a better, more "noble" answer, I'd love to hear it.
> obtain enough passive income to be independently wealthy
"Passive income" does not make you "independently wealthy". You avoid "being forced to sell [your] time" because you extract wealth from those who do.
Rent seeking does not, by definition, involve "creating value":
In economics and in public-choice theory, rent-seeking involves seeking to increase one's share of existing wealth without creating new wealth. Rent-seeking results in reduced economic efficiency through poor allocation of resources, reduced actual wealth creation, lost government revenue, increased income inequality, and (potentially) national decline. - Wikipedia
From Taking Back Adam Smith and “Classic Liberalism”:
Many conservative economists claim to be staunch followers of Adam Smith. They shout slogans such as “Supply and Demand!” “Capitalism”! “ “Let the markets work!” However, for anyone who actually read Adam Smith, you would note that the “invisible hand” was not his only observation of the inner workings of capitalism. Adam Smith recognized that many in the economy were making gobs of money, but weren’t contributing anything. He was referring to what was eventually called “economic rent”.
Smith observed that all production required 3 things. Land, Capital, and Labor. A very simple example would be a brick factory. The building and oven needed to create the bricks are the “capital” – the owners are the capitalists. The people making the bricks is the “labor” – the people doing the actual work. The Land the factory occupies and the clay used to make the bricks is the “land” – the owners of the land are the “Rentiers”. Any money made by selling the bricks is then divided up between these three groups: the rentiers, the capitalists, and the workers.
Where many here on HN and I will differ is what forms of passive income are rent seeking rather value creating applications of the output of one's previous labor.
Note that you can even be pro-Capitalism and anti-rent-seeking: How Economists Duped Us into Attacking Capitalism Instead of Parasitic Rent-Seeking http://evonomics.com/economists-duped-attacking-capitalism/
Are you a Real Libertarian, or a ROYAL Libertarian? http://geolib.com/essays/sullivan.dan/royallib.html
