> clearly explained in the first paragraph of the readme

Yeah but people justifiably don't exhaustively read documentation. If people are getting confused because they didn't read some bit of documentation - even the first paragraph of the readme - then you shouldn't just dismiss them as stupid and bask in your superior documentation-reading abilities. You should think about how to resolve that confusion in a way that they would actually see it.

It's hard to explain how to do that without a concrete example, but it usually is possible. It's also usually more work than just replying RTFM, but you should at least be aware that you are choosing not to bother.