They aren't flawed but they are common. Chocolate diamonds, also known as Brown diamonds, are the most common color for diamonds. Basically the whole thing is a scam to get people to pay high prices for a common diamond. Stay away from the name brand jewlers... KAY, Jared etc.
I mean, diamonds range in colour from yellow to white to red, depending on the inclusions within the carbon lattice. Brown diamonds are very common. Diamonds are quite common anyway; carbon is the most abundant mineral in the universe (or at the very least on earth) so they shouldn't be as expensive as they are. That's the artificial scarcity created by the De Beers company for ya.