Crazy! You made me remember i actually once paid for "something" when it comes to Whatsapp! Then they added somekind of disclaimer "will be a paid service xxxxxyyyy" but it never happened!
I think it was more or less “nag ware”. I remember clicking “no, later” multiple times in a row and they’d only ask like twice a year. I don’t think it ever stopped working for people who didn’t pay (afaik).
Yes I don't remember what I paid for.