It’s as reliable as the sun rising: Whether he’s macking on Xandarians or leading the Army, Stan Lee cameos in every Marvel movie, and not just the Avengers end of things, either. It’s a little nod to the fan and something of a tradition in modern Marvel movies. But what if Smilin’ Stan isn’t just cameoing?
For non-nerds, that’s Uatu, the Watcher. He’s pretty much a historian that observes notable events and records them for posterity, and is sworn not to interfere. Which he totally does anyway, all the time.
It’s a fun theory not least because it would mean there’s a Marvel multiverse, and Stan serves as the connecting link between all of them. No matter the time or the place, there’s Stan, keeping an eye on things, and, if studios ever give up and decide to give us the massive crossovers we want to see, he could even be the facilitator of such a blow-out.
Of course, this would potentially mean that Kevin Smith would try to force the Askewniverse into Marvel, by insisting Stan Lee was in his movies, too. So maybe we should just let this fan theory stay that way, for now.