It was first used as a pejorative by customers of White Castle; it spread to other uses from there, and just fairly recently White Castle started using it themselves, trying to substitute their manufactured, fake-cutesy meaning of “so small it slides right down” for the original, much more accurate “they slide right through you”.
I heard the term used in the pejorative-for-WC sense decades before it was applied to anything else. That includes hearing it thus used by former sailors from before your service.
The 1950s were not only the period of the highest rate of unionization, but also had a top tax bracket of over 90%.
And it was the period of the strongest economy in US history, and saw the creation of the middle class as we know it (or at least knew it, before Bill Clinton sold the Democratic Party to Wall Street, leaving the 1% with about 99% representation in government, and the 99% with 1%).
While it has in recent years been appropriated as term meaning “really small sandwich”, it properly refers only to White Castle “hamburgers”; the etymology is that they were so dubbed because they slide right through you.
I have eaten alligator, rattlesnake, and (I’m pretty sure) cat*; all were delicious.
*It was a taco from a street cart in Nogales, Mexico – not in the 3 blocks of tourist crap; back where no one spoke English any more than I spoke Español, so no IDing it wasn’t possible. It was a meat I’d never had before, nor have I since. Though I suppose iguana is a possibility, too.
It was first used as a pejorative by customers of White Castle; it spread to other uses from there, and just fairly recently White Castle started using it themselves, trying to substitute their manufactured, fake-cutesy meaning of “so small it slides right down” for the original, much more accurate “they slide right through you”.
I heard the term used in the pejorative-for-WC sense decades before it was applied to anything else. That includes hearing it thus used by former sailors from before your service.