When I worked in New York City
back in the early 70s
I used to witness at regular intervals
of what constituted "regular coffee".
You must understand that in NYC speed is very important:
when you enter a deli or other purveyor of comestibles
and potables, you are expected to bark out your
order without hesitation or thought, and you expect
in return rapid service in a small brown bag.
So, it would go like this:
Athenian Stranger: I went into so-and-so's and
asked for regular coffee, and what do you think they
Interlocutor A: One cream, two sugars?
Athenian Stranger: That's not regular coffee!
That's what they gave me, but that's not regular coffee!
Regular coffee is one milk, no sugar.
Interlocutor B: What are you talking about?
What you described is "slim, no sweet". Regular coffee
is black, no sugar.
Interlocutor A: No, that's "black, no sugar"...
And so it would go. Of course, my contribution* was
always discarded out of hand
*Regular coffee is not a technical term;
what it refers to depends on where you go.