The big North American chains (Starbucks, McD, Tim Hortons, Second Cup, Van Houtes, etc.) push a "dark roast" as their somehow gourmet option. In all cases these are cheap old beans that have been over-roasted so that 'burnt' stands in for flavour.

Many people have taken that experience to mean all dark roasts are bad, when in fact it's not the same thing as buying a fresh darker roast blend from a local roastery.