I have a question about the Paul is dead conspiracy?

So I don't believe the rumor but it's weird because people say that The Beatles purposefully planted clues in albums such as Sgt Peppers to mess with people who believed the rumor but the rumor didn't even get out until AFTER the release of Abbey Road (their last album) and then didn't people go back to look for clues? It doesn't really make sense that they planted clues just to mess with people then... the rumor either didn't exist back then or at least wasn't know to the public. I still don't really believe it though.