Is Steemit a Ponzi scheme ?
Many people is wondering why some account on Steemit has more than one million Steem Power, while we just start with ten.
Will it be possible for a user registering today, or the next year, to reach 1 million Steem Power ?
If it is not possible, this would sound pretty unfair for a service that aspires to revolution the social networks and the world economy.
As a poker player, I would never sit in a game where my opponent has an opportunity to collude, or to know my cards. Because such a game can't be beaten.
Instead, I would probably sit in a game where my opponent is likely to be a tougher player than me. Because I know this is the only way to improve my game, and to get precious informations about the best players in my game.
Also if the founders of Steemit have reserved for themeselves a big part of the cake, we can be optimistic about the future, because if they try to transform this site in a speculation, they will just sit with a ton of Steem in their hands... but Steem will be worth nothing!
Let's see better how a Ponzi scheme works:
A guy, let's call him Charles Ponzi, offer the chance to make a very interesting investment, offering a very big interest rate. For example 5% every month. People start investing small amounts of money, and Ponzi repays their investment. As the market start believing in this investment, people start committing an esponential amount of money. Mr Ponzi pays the interest with the money of new subscribers. At a certain point, he runs away with the money.
Why Steemit can't be like a Ponzi Scheme ?
the answer is simple:
because doing a similar thing with Steem would just decrease the value of Steem. So mr Ponsteem... would not gain millions of dollars, but millions of a currency worth just nothing!!!
For sure the reward system will need some fix to avoid that only the most powerful accounts control all the system: we aren't here to enrich a new Mark Zuckerberg with our own work. But I believe we can be optimistic regarding this changes, because they will be profitable also for the accounts with more Steem Power.

The problem of any ponzi scheme is, that its getting harder and harder for Mr. Ponzi to pay the interest for his investors. He needs new investors to cover them. Cryptocurrencies are different, because they don't pay interests. They crash, when they don't reach enough market size (and so you can hardly use them) or when there are big technical security issues. Of course the price can be very volatile, but thats because of speculation mainly.
I personnaly think every cryptocurrency can be compared to a ponzi scheme but with a slight twist. The value of each is only guided by how much new investors are willing to pay for it. Whatever money you make with bitcoin, steemit or any other cryptocurrency is only worth the price you will be able to sell it for so without new investors, all the cryptocurrencies would be worth zero...
if you look at currencies from that perspective, every currency works like that: also dollars, euros or whatever.
But this is what make currencies interesting: they are useful to make exchanges of goods and services.
I see your point, the difference is you don't decide to invest in euros or dollars or maybe you can if you are a trader but most people are just told that this is what they have to use and accept it. Until the cryptocurrency revolution...