I don't know of any rhyme, but I always assumed that this was a reference to the Hitchhiker's Guide and Sirius Cybernetics Corporation. Which, yes, does involve a pig: https://www.goodreads.com/quotes/95859-share-and-enjoy-is-th...
Sirus Cybernetics Corporation was best known for having created Marvin, the depressed android, and doors with cheerful personalities:
> “All the doors in this spaceship have a cheerful and sunny disposition. It is their pleasure to open for you, and their satisfaction to close again with the knowledge of a job well done.”
So yes, "Share and enjoy" was originally deeply drenched in irony, and it functioned as a warning to proceed at the user's own risk.
If you don't give any guarantees beside "it's a hobby project", you can't expect anyone else to use your software beyond hobby projects either.
I am happy to provide consulting services and support guarantees through my LLC, and have done so in the past.
Non-paying users who ask nicely might get fixes. Or they might not! Unfortunately, those fixes might also arrive a year or two after they stopped caring, I'm sad to say.
But a project which doesn't bring me any revenue, and which doesn't function as valuable advertising, is only going to receive support when I have the time and the inclination.
Realistically, commerical adoption is only interesting to me if there's some upside for me. This isn't to say that companies should never use my libraries or tools. Just that if they want timely support, they should be prepared to either pay me, or use the "Fork" button.
Can't speak for log4j, but I don't expect anyone to use my SW beyond hobby projects. If they do, I expect them to be responsible for how they use it.
That's a good thing. The companies shouldn't be expecting free code and free support. If they want something for a commercial product, pay for a commercial library with a support contract.
It isn't. Every open source consumer is ultimately responsible for the use of the code. That's baked into every open source license I'm aware of. Even the "share and enjoy" mantra is a tongue-in-cheek reference to a rhyme that ends with recommending what porcine orifices you can put your head on if you don't like the software.
... But there's more to be gained by the original authors, in glory and internet points, by publishing a fix for the problem than in washing their hands of the whole affair. Some people want their code correct as a point of professional pride alone.