Of the world's over 7 billion people, how many can today afford or even practically buy bitcoins? Not many percentage wise. And someone said that 70% of the U.S. population today don't even know what bitcoin is.
So how is that fair? It isn't. Because the opportunity to buy early is very lopsidedly distributed in society.
What about in the future? Let's say that a fraction of a percent of the world's population become very wealthy by having bought bitcoins early. The price of one bitcoin has become extremely high. Would that be a fair monetary system? Could be!
Why? Price/performance is progressing exponentially for information technology, and as Ray Kurzweil has pointed out, even material goods are becoming information technology.
This means that within a few decades people will be able to 3D print a Big Mac for free. And a decade after that, a flying Ferrari can be 3D printed for free. And then how many bitcoins you own will not matter that much. Ha ha.