I've tried to explain this all the time.
The fact that a coin has a premine doesn't make it scam in the first place. It is just the seed fund/starting capital of the project and means to pay to the developers.
That being said, I advice to be extremely critical to the coins with premine - the premine is incentivizing scammish activities (dump the premine to the noobs and run to the next scam). To claim Dark coin a scam is using the same logic that a start up is a scam because it has initial funding from the investors.
When it comes to pyramid schemes, any coin is a pyramid scheme: the new buyers bail the current holders/miners out. So in that sense Dark coin is not a scam either more than any other investment. Quite the opposite, the pyramid is the form of investment that can make one rich.