Let’s analyze the clientele of each of the establishments. When you think Starbucks, you think celebrities with venti lattes walking through Hollywood, or extra-hot-soy-caramel-no-whip-macchiatos. Dunkin Donuts? I see the working mom on her way to work rushing through the drive-thru, or a “regulah” coffee with “cream n’ sugah.” (At least that’s the way it is in Massachusetts). It’s clear that the clientele of each company is different. The message that the respective chains are trying to convey is different, and they are attracting their type of people through their logos. They are branding their product. The logo, however, cannot be something obscure that requires a lot of detail—it needs to fit on a coffee cup. That is where typefaces come in.
When I look at the Dunkin Donuts logo, the bright colors attract me. However, the font of the text is the most important thing. The designers of this logo opted for a rounded font, which isn’t necessarily childish, but it reminds me of something a bit less serious. It is welcoming, unpretentious, and less assuming. Take a look at the Starbucks logo. The woman in the center draws allusions to mythical characters, and the sans serif, large block typeface is very serious and more sophisticated. The typefaces play to the clientele of each company. 
Starbucks sells a higher-priced, “fancier” type of coffee, and they have a fancier, almost more-educated type of logo. Dunkin Donuts has a less expensive, more home-y, and regular person-feel to their logo. This isn’t to say that only a certain type of person drinks each type of coffee; people should choose the caffeinated beverage that is most tasty to them. However, I’m sure that much of America is more concerned about the image of their cup than what is inside of it. Either way, (and it should be no surprise) both Starbucks and Dunkin Donuts have successfully used typefaces to sell their products across the United States and even around the world.
