Reading this thread gave me an interesting insight into the world I live in that is not mainland USA. Sometimes paying for dinner, lunch, snack or coffee is a cultural thing, and not one that can be ignored.
A school pal and I often go out to lunch before or after studying. We usually just pay our own way - no worries. One day we went someplace that only took cash and all I had was a cc (not ATM) card on me because I forgot my wallet. I keep a back up card stashed deep in the bottom back pocket of my bag because well.. I'm forgetful..
So anyway - it wasn't a big deal I just decided to forgo lunch. She said no, I said yes, she said no, I said yes, and finally she looked at me and said "this is Hawaii, it's rude for me to eat alone, so pick something or I'll pick for you, but I'm not eating alone, don't be rude!" (I don't eat fish and she does, so I picked out of fear of being stuck with seafood soup!) Since then - we don't question if one of us doesn't have cash or is broke we just eat because it is the culturally appropriate thing to do.
The above is a deviation on what has been discussed - my point is that our views about "a simple cup of coffee" or "just a drink" and "the value of time" are, like all things, inherently affected by our culture. Not just the culture(s) we grew up with or the ones we live in/adhere to as adults, but also by the cultures of the people we interact with. Hence we have differences of opinion about something as seemingly simple as "a cup of coffee".