Maybe I am in a different academic field that
doesn't emphasise the train of sources, but I have never referenced the articles that
I used to get the sources I use for quotes or ideas in my articles... Nothing personal
against authors who have really good reference lists, it is just that I reference ideas
directly without the chain of evidence I guess.
As a student (of mathematics), I've been subjected to the standard
lectures about not plagiarising, and I don't remember anything about
having to cite the sources of your sources. I wouldn't cite a
Wikipedia article that was just used to get me started as wasn't the
actual source of any facts included in my work.