Apparently it doesn’t matter if it's associated with a digital purchase or not. They consider zap button on a post = associated with the content even if the receiving user doesn’t know its from a post. okay…

I guess they have their own unwritten guidelines that you have to follow nostr:note1jt44nnqh2exr2s99ffhk0vut8axgkmgzm5uf6ymsz2fjvrxpdg0s4v6lz8