This is true to the most part, but this does not mean all darker roasts are from cheap beans.When you buy cheap beans you have no choice but to roast dark.
If you look at places that sell light or medium light roasts those beans usually cost more.
That said, I've had **** beans from all the larger roasters. Broken dregs. WTH???
Buying already ground coffee is just nuts IMHO. It already smells of acid. They could be grinding dregs.