Kind of surprised this is a thing: seems like showing up with a 5$ bill or credit card and getting coffee and change back (whether from a human or from a coffee vending machine) would be a fine process. If one is a regular coffee drinker and finds that inefficient, buying a coffee machine for home/work seems like a better solution than attempting to "order ahead" and still having to physically get to the coffee shop.…
Also, Starbucks is on pace to process over 15% of their annual revenue through their mobile app this year, it's by far the most popular payments app in the U.S. and shows no signs of slowing down.