Going by some arguments in this thread, to ask a restaurant to be considerate for a section of the population is considered entitled but being a cheapskate and selfish money guzzler is a god given right and should be something to be proud of. Like, it doesn't even cost the restaurant $1-$2 extra per serving. Of course, when it comes to money.. fuck being considerate right?
I used to work in restaurants (both big and small), and while what you said is true, it only cost $1-2 extra per serving. But the restaurant can never stock their ingredients by "per serving". They have to buy wholesale from their suppliers. It really hurts smaller businesses when they only get to use a couple servings out of their 5 gallon non-dairy milk jug, then have to throw it out. Those things added up fast, and that's just one example.
they only get to use a couple servings out of their 5 gallon non-dairy milk jug
Don't buy so much at one time then? Doesn't seem that difficult a problem to solve, I do it every time my dairy-averse partner stays over for the weekend. Buy an amount that is reasonable for expected usage needs, it's easy. I'm not out here buying a 5 gallon bucket and then whining when my guests haven't drank all of it.
I don't know what the profit margins of Starbucks are, but in many cases they're much tighter than people realize. The sale price has to cover materials, wages, insurance, property costs, and lots of other things. $1 a serving would be a pretty huge percent increase.
You could make the same argument about anything. I want the higher end iPhone and they should give it to me for the same price as the lower end to be considerate. If they don't they're greedy. I want leather seats in my car for the same price as cloth. And there are loads of restaurants that charge extra for substitutions if the substitute costs more (e.g., "premium sides").