People in general are harsher than this community. A lot people call bitcoin a ponzi scheme. They wonder why they should invest just line the pockets of early adopters. The same thing will happen to dark. Without a relatively flat rewards schedule, people dismiss it as a ponzi. Sure, some will buy in, as you can see with bitcoin, but it hinders mass adoption.
I understand that. But those who want to pull the ponzi argument, they can use it for every single coin, whether it's bitcoin, litecoin or anything. Because the logic is still there: The buyer who bought at 1$ needs a buyer at 2$, who'll need a buyer at 4$, who'll need a buyer at 8-16-32-64$ to make 100%. The stock market, real estate, all are called "bubbles", in the same sense. Someone is waiting for another to buy his own stuff for more than he bought it. If it doesn't happen the bubble is burst.