I follow it on RSS, it's sometime's funny but not required reading.
I don't think you can blame the comic's author for people on HN and elsewhere passing around references to specific comics to make their points.
As to the specific one mentioned here, I don't remember reading it before.
edit to add sometimes it's obvious the entire joke is in the alt-text, like so: https://xkcd.com/3143/
Enjoy this Rat pitch for a "pastor" who shall spread the gospel of Bayes to the unwashed masses:
https://www.lesswrong.com/posts/crEduvg2DwHPP74cw/pastor-selfie-an-attempt-to-evangelize-lesswrong-concepts-on