I'm confused about what you're calling sweet. Plain coffee, however you brew it, doesn't have sugar. What are you ordering?
I suspect my tastes don't match yours. I'm a French or Italian Roast fan, the darker the better. "Jet fuel" to some.
And, ahem, not to sound picky, but frappucino isn't coffee by any stretch of definition. It's a chemically formulated sugary coffee flavored imitation milkshake drink with excellent marketing.