As a Starbucks barista, I can say that it is test market in Seattle for a short (8oz.) coffee. The regular price is $1.50. As part of our "Just Say Yes" beliefs, at least in our store, we will honor that price if a customer requests it.
Refills for coffee/tea are usually 50 cents, regardless of size, as long as you are in the cafe-coming back after 2 hours is not a refill. If you have your own mug, you'll always get a 10 cent discount on your drink.
Personally, I am not afraid at all of Mc Donald's or Dunkin' Donuts. I wouldn't order a burger at Starbucks, so why would I get a latte at McD's? You go where a place does something well-sorry I'll never see McD's as a "third place" where I'll go relax, chat with friends over a nice latte. Starbucks has better music also!
DD, I like their donuts, coffee is weak but ok, and I've never liked their espresso drinks.
Starbucks has great principles and benefits. After all, that's why I went from customer to partner!