Has anyone noticed that the Coen brothers' movies have the same basic story lines?

Not to diss the Coens, because they are good directors but they say they like to subvert "genres" they basically seem to use the same plot in different settings. All their movies are about some insanely stupid planned concocted by dumb people, usually involving snatching money or something valuable from its owner, and everything that can go wrong, does. Think about it: Fargo, Raising Arizona, No country for old men, and burn after reading, each has a dumb character who steals/scams and pays dire consequences for it. They also have the same unstoppable, psychopath: the lone rider of the apocalypse, the swedish guy in fargo, the sheriff in oh brother where art thou, and antoin chigur. They're all basically the same guy! Again, the Coens' movies are good. I just think that they're copying themselves.