The jokes we know are funnier than the ones we don't. The unexpected is only funny once. The familiar has scope to be funnier, because it allows you to tell it artfully. Otherwise, all comedy would be jokes, rather than character, situation and observation. The funniest thing of all is being told something you know, as seen from a slightly different angle.
Even funnier than the funniest thing of all is being told something that isn't funny, but in a way that makes you laugh. That's real comedy. I'm working on it.