You make a really good point about paper receipts – in many cases they're coated in the PFAS chemicals.
I don't agree with reducing the importance of the issue by writing it off as an Internet craze. News & research reporting of all kinds hits the Internet, but in this case people talk about it because of high quality scientific research that has identified a likely concern for human health. I agree the level of harm is debatable, but the substances have been shown to bioaccumulate in humans.
Take a look at the
'Results from studies on humans' section +
'Table 2 Toxicological results on humans' table in this peer-reviewed journal article:
enveurope.springeropen.com
And I agree that for some people, they may not care that much due to their personal health journey. But looking at it from the perspective of improving the health situation for people in general
everywhere, or even potentially just as a parent, it's worth considering at the very least.
I also like your point about contradictory reactions to different health concerns, and there is definitely a degree of hype about certain issues at particular times which then seems to be forgotten about by the masses (often because it's more convenient to revert to easier habits).