The Problem
Even a fresh drink still asks you to just believe the menu board.
Most coffee shops do make your drink fresh, to be fair, and plenty use a clear cup too. But a cup you can see through only shows you the finished drink, not how it got there: how much syrup went in, what's really in that syrup, whether it matches the menu board the same way it did last time.
We didn't want to ask you to just take our word for it.