You've not seen the one from Marnie have you? Or North by Northwest. I would count his cameos as in exactly the same spirit as the Stan Lees ones, a bit of a fun nod and a wink to the audience, and they are certainly often less-than-subtle. Besides, Stan Lee being front and centre is the whole point! The Marvel films are meant to be fun. They're not, ultimately, meant to be taken remotely seriously. Stan Lee's inclusion just underlines this. They always make me smile and I can't think of a single one where his inclusion hasn't made the film a little bit extra special.