The cafe way to save water

For some reason, the servers at cafes the world over are always afraid to actually fill up a cup to the top. I mean, I love Nook for a great many reasons (such as outdoor seating, cheap drinks, and the joy of watching tourists screech around the corner on the cable cars) but even there, the servers never want to fill up my cup. Take a look at the tea I got on a recent outing below. That’s something like 2/3 full. It’s really not like they’re saving money by doing this. The expensive part is that bag floating in there. It’s the same for coffee as well in that they rarely fill up the cup and it’s the coffee beans that are the expensive part.
Sometimes I’ll ask to get a fill up to the top and they’ll oblige most of the time without a huff or sigh. Other times, the place offers free refills, but will still give you these meager cups. I don’t get it. I just don’t get it.
The cafe way to save water