Tipping at Starbucks is not like tipping a bartender because at Starbucks there is an exact way they have to make your drink. Whereas a bartender might poor a little extra alcohol in your mixed drink, a barista is not going to hook up any extra espresso or probably even think that you would want any extra. Starbucks is not freehand drink making, they go to school and learn exact proportions for uniformity of product. I recommend stealing the tip jar and giving it to one of the people who ring the bells at storefronts. I would never tip a coffee maker, same as I don't tip a bartender for opening a beer. A tip is money for service above and beyond, and all too often it's expected. I have ZERO problem not tipping, and I have worked in the service industry before.