Even though DD works for Teavana (owned by Starbucks), I refer to SB as "Charbucks" as most of their coffee is too dark and tastes burnt. Their blonde roast isn't too bad, but give me Dunkin' Donuts anyday.
Best way around "bitter" coffee...buy a reusable K-cup for the Keurig (Walmart sells them) and fill it with any coffee you do like. Much cheaper than the prepacked K-cups and you can use the coffee you like. (Reusable is also better for the environment - less plastic going into the landfills).