In answer to your comments:
(1) I don't know everything. However, I am English, and wanted to make that clear so that the other readers of the forum would understand that this was the opinion of a native speaker. It is an indicator of the language level of the poster. Sometimes this helps; for example, Claudia or WH could be German, or some other nationality. I would not regard it as pompous, for example, if someone wrote "As a language teacher" or "as someone who has spent 5 years in the country".
(2) You describe WH's posting as "funny" and "completely false". I don't think it is. You also permit yourself to take a jibe at another poster (me). But before casting judgment on others, don't you think that the following (selected from your comment) might undermine your credibility somewhat:
- "just read your comment": English sentences start with a capital letter. This includes the first line of a letter or posting, even though the introductory line (e.g. "Dear Sir," or "Hi John,") ends in a comma.
- "english": in English, this should also start with a capital letter.
- "Joghurt": in English, lower case and with a "y" not a "j". The "h" is optional.
All of these are typical errors derived straight from the German. Are you German? Even the German contains an error:
- "umgangssprache": this should also start with a capital letter.
(3) I repeat, I have *never* heard "expired" used in conversation in this context. On the label, yes; spoken, no. Not even colloquially. It may be common where you speak English, but I have never heard it. (This also applies to American and Australian English.) To claim that "this is what one commonly says in conversation" is not true. It would be more accurate to say "this is what I commonly say/have heard in conversation". This isn't a judgment of your English, it is simply a statement of fact.