Waiters and and other servers here, in situations where I would say, “I’m sorry, we’ve run out of x,” tend to say, “X is finished.” Since that’s not a literal translation of the Vietnamese, I’m confused where they are learning it. Before I try to correct them, would that be the correct British English expression? It sounds very strange to me!
Amusing side note: I was at a rather upscale bar here and ordered a Cosmopolitan. (Hey I like them, all right?) The waiter came back to say the cranberry juice was finished, and asked if pineapple juice would be OK. After I finished laughing, I agreed. The resulting concoction was just about as awful as you would expect.
. “I’m sorry, we’ve run out of X” sounds more like British English, I’d say. “X is finished” doesn’t sound like British English to me
My WAG would be, given where you are, that it might be translation into English from a French construction.
“X est fini”
I’m not saying that the person you are talking to knows French and is tranaslating from French to English to talk to you, but maybe that’s how he was taught English, from someone with some sort of French twist.
Funnily enough, I was told yesterday by a waiter (in London) that “the chocolate cake is finished”. Which is only anecdotal evidence rather than proof of proper grammar, but there you go.
Even better is the phrase you still get in some, shall we say, downmarket establishments: “X is off” (as in “off the menu, because we’ve run out of it”).
Interesting replies. Maybe it does come from French, which was extremely popular here in past generations, but now is in a severe decline. Some of the older people still speak it though, so that’s a possibility.
I never knew “off” meant “ran out of”. In that Monty Python sketch, famous for introducing the sense of “spam” that eventually applied to junk e-mail, the waitress says, “The baked beans are off.” I assumed she (or he actually) meant they had gone bad. You learn something new everyday, even if it’s not what you were asking about.
Any confirmations for, “The cake is finished?”
Another WAG:
People have finished (= eaten) the cake, so the cake is finished. Does that make sense?
Before I try to correct them
Just a personal pet peeve here about manners. It is extremely rude to correct the grammar of someone who hasn’t asked that you do so. And on top of it, FYI, your question actually has nothing to do with grammar and is really a usage question. If it were me and you tried to correct my grammar, I’d let you have it both barrels. I’d tell you to learn something about what grammar is before you try to correct someone and that you learn some manners on top of it.
</rant>
It’s common for idioms to be translated literally from one language to another. My Indian relatives, for example, don’t say “We’ve run out of chicken curry,” nor do they say “The chicken curry is finished,” nor do they say “There’s no more chicken curry.”
They say “The chicken curry is over.”
Wow, daffyduck. This isn’t the Pit! If it were, I might suggest you try paying attention before you start blasting away. I live in Viet Nam. People who talk to me are not native English speakers, but are desperately trying to learn it. In fact, many people do ask me to correct them. I’m just trying to make sure I pass on good information.
Anyway, I think you’re splitting hairs with the grammar vs. usage thing. According to Webster’s:
grammar: The art of speaking or writing with correctness or according to established usage
On this Board, we’re always careful to make the distinction between grammar and usage.
Besides, you’re being awfully disingenuous with that definition. Here’s a fuller version, from dictionary.com:
Note that both definition refer to the rules of a language. Your question had nothing to do with rules.
On that same page is a much better set of definitions from American Heritage, and they don’t support you at all.
Back to the OP. I think that others have it correct. “is finished” is not good idiomatic English anywhere. But it is a simple formulation, and probably less confusing to a non-native speaker than a prepositional phrase like “out of.” Prepositions are often extremely difficult to grasp, and the basic “to be” verb is straightforward.
Nothing to add here other than that in the places I’ve worked the term was “86’ed”, as in “The tenderloin is 86’ed.”
Point taken … but I still think the difference between grammar and usage is relatively small and not deserving of a flame. A correction possibly, but not a flame. That we are always careful to make that distinction on this board, I was unaware. Not launching personal attacks in GQ, however, is a rule, and not to be ignored lightly … you know, unless the other poster really deserves it. 
The tally so far then for, “X is finished,” being correct usage:
one vote for, one vote against.
I’m not sure about it being easy to grasp though. The first time I heard, “X is finished,” I said, “Well, that’s good, then please serve it,” assuming they meant that had finished cooking it. A more literal translation of the Vietnamese would be, “X is gone,” which would be clearer.
Interestingly (or perhaps not too interestingly), Scandinavian languages use the same construct: as in Norwegian, “slutt på X”, which implicitly means the supply of X has reached its end; it’s used in the same way as the English out, as in “we’re all out of milk”. I suspect a lot of language has this rather literal translation of the concept of running out.
I’ll plump for the French derivation.
I think of “finished” as applying to a process that has reached an end: “My work is finished,” or “the laundry is finished.” If someone were to say, “The chicken is finished,” I would assume they meant that the process of cooking the chicken has come to an end, not that there is no more chicken available.
The only exception I can think of would apply to something like furniture: “This table, unlike that raw pine number over there, is finished.”
(OK, let the myriad counter-examples fly, and make me look like an idiot!)
They might find the idiomatic expression “run out of” to be very curious and associate it more with “to exit quickly.” Since they most likely have been around both English and French speaking people all of their lives and have developed their own idiomatic usages, I see no reason to try to change this language pattern. Since by your own words they tend to say that something “is finished” and that makes just as much sense, if not moreso, why not leave it as it is. It is not ungrammatical.
I find idiomatic usages delightful. My granddaughter invited me to “lick the windows” in Paris. That’s the literal translation of the French words for “window shopping.”
Curious: What is the equivalent French phrase?