Pig in a Poke, Cat in a Sack, Fish in Water, ...

[Speakeasy]

Cross-Cultural Idiom
Earlier today, in a separate post, I commented as follows: "I deplore what-seems-to-be the increasingly generalized practice on the part of the major online booksellers of listing their wares under incorrect ISBN's, edition numbers, titles, authors, and the like. This practice, coupled with their refusal to provide clear answers to simple questions, means that one is frequently left with choice of either "buying a pig in a poke" or simply doing without."

Although I have not heard anyone use the idiom "buying a pig in a poke" for years, I used it in my post because, having learned it as a child, it came to mind so easily for me. About an hour after posting my comment, I decided to Google the idiom and, to my surprise, I came across a Wikipedia article which explains its origins and offers equivalents in a fair number of languages.

Pig in a Poke - Wikipedia
https://en.wikipedia.org/wiki/Pig_in_a_poke

It occurred to me that some other members might find the article interesting. Going further, perhaps some members would wish to comment on the use of the variants of this idiom, be they in English or in any other language. For example, has "pig in a poke" been replaced by something more current in English? What about the other languages listed in the article or the idiom's equivalents in languages not listed?

Afterthought:
Frankly, the similarity of the "cat in a sack" idioms across so many disparate languages seems a little suspicious to me. Did all of these societies share a experience of piglings being offered for sale "sight unseen in bags" only to find that cats had been surreptitious substituted in a "bait and switch" operation. Was this pratice so universal that the idiom "cat in a sack" developed in so many of these linguistic groups? To me, this seems highly unlikely. I find myself wondering if the person who wrote the Wikipedia article merely translated the idiom from one of the languags and then transposed it into/onto the other languages. Comments, anyone?

[Brun Ugle]

Well, you taught me a word — pigling. I’ve only ever heard piglet.

I can confirm the Norwegian version, å kjøpe katta i sekken, to buy the cat in the sack. It is still used regularly and is also something you find at charity bazaars, where you can buy some unknown item that’s already packed in.

[hedgehog.chess]

I can confirm the German "die Katze im Sack kaufen" (at least I encountered it) and Polish "kupować kota w worku".

[Speakeasy]

Well, you taught me a word — pigling. I’ve only ever heard piglet...

I typed "pigling" without really thinking about, something from my childhood, I guess. WikiDiff explains the difference between "piglet" and "pigling", with little eloquency, as follows: "As nouns the difference between pigling and piglet is that pigling is a little or young pig; a piglet, while piglet is a young pig; pigling." Hmm, something that Data might have said ...

IMAGE
Data: a pigling is a little or young pig; a piglet, while piglet is a young pig; pigling.

[tarvos]

Een kat in de zak kopen in Dutch.

[jeff_lindqvist]

The Swedish expression is still in use - köpa grisen i säcken.

[tarvos]

Men en gris är ju ingen katt.

But a pig is not a cat at all!

[Speakeasy]

Men en gris är ju ingen katt.

Jag ska sälja dig min gris, osynlig syn.

[tarvos]

Nej tack, i säcken ska man nog inte köpa djur.

[Xenops]

For some reason, "monster in a sack" doesn't sound as good as "pocket monster".