The following question is not rhetorical. I do not have any good way to reason my way to the answer but feel it might be important in my future professional dealings with American coffee drinkers (a social situation I have literally never been in before).
What does not buying someone coffee tell you about them? Does it matter that this took place in or outside of his office? Does it matter that he invited you?
[Edited to add: Oh, I live in Japan. This might be interesting to some of y'all: here, the boss outranks the job applicant and is almost certainly the host rather than the guest in this context. Thus, it is his social responsibility to arrange for tea or coffee for his guest. The guest should probably decline the offer once before accepting it.
Not offering the coffee is a fairly significant breach of etiquette -- it would cause me to wince hearing the story. Buying your own coffee, on the other hand, is about a step short of slapping him in the face. It says "I noticed your lapse of etiquette" and, more importantly, "I just called you on it." Given that a guest has bought himself coffee, the polite thing to do as the host is to take no notice of the fact.
In a business relationship, even if it's a totally impromptu coffee break, the man should have offered to buy him one. Anything else is either cheap or inconsiderate or at least unschooled in the way of proper manners.
We have a rather excellent coffee shop on the first floor of our building, and so coffee shops are the setting for almost all of my meetings with candidates and business associates.
I'm thinking back trying to remember a time I invited someone over and didn't buy. Nothing comes to mind, but I couldn't 100% promise you that I managed to buy every time.
I'm not doubting JGC learned something about that CEO from the fact that the guy didn't buy him coffee, but in America, sometimes not buying coffee just means forgetting to buy coffee.
I've always liked the waiter test for salespeople, though: tip a waiter $50 to handle the candidate poorly, and see whether the candidate remains respectful. I know I've never snapped at a server before.
What does not buying someone coffee tell you about them? Does it matter that this took place in or outside of his office? Does it matter that he invited you?
[Edited to add: Oh, I live in Japan. This might be interesting to some of y'all: here, the boss outranks the job applicant and is almost certainly the host rather than the guest in this context. Thus, it is his social responsibility to arrange for tea or coffee for his guest. The guest should probably decline the offer once before accepting it.
Not offering the coffee is a fairly significant breach of etiquette -- it would cause me to wince hearing the story. Buying your own coffee, on the other hand, is about a step short of slapping him in the face. It says "I noticed your lapse of etiquette" and, more importantly, "I just called you on it." Given that a guest has bought himself coffee, the polite thing to do as the host is to take no notice of the fact.
We have manuals for this sort of thing.]