That’s always puzzled me and Snopes says it’s false.
Yup - you'll still see a sign on every forecourt though. I got yelled at about 6 months ago for using my phone whilst fuelling at a Sainsbury's Petrol Station forecourt (I was on a Conference call and didn't really give it a second thought). Loud woman wasn't having it at all. "it's illegal" (it isn't), "it's dangerous" (it isn't).
I did snap a little and ask if she had a mobile phone in her pocket and if so, was it switched on?
But as I said, I get massively annoyed by airline staff making you put your phones / laptops / tablets away for takeoff.