I've always preferred Dunkin Donuts to Starbucks because it has a more business-like and less-bohemian atmosphere. You can order your coffee drink in two syllables without sounding like a rube. Over at Starbucks, you have to wear sandals, sport a goatee and use five or more syllables to describe your drink in order to be accepted as a member of the cognescenti.
That said, I do have some guilty pleasures over at the Starbucks such as their pumpkin-based lattes.
I’ve never been to a Starbuck’s. (No ideology, just not a coffee drinker.) When I go to a Dunkin’ Donuts, all I want is donuts. (And iced tea if I’m eating in.)