I assume the Swiss Army knife, invented in 1891 or so, was patented. But as Tim Lee says in this post at The Technology Liberation Front, "If there's prior art for the individual blades, then the knife is obvious, even if no one has happened to sell a knife with that particular combination of blades."
And why should we believe that the inventor's first mover advantage and entrepreneurial moxie couldn't have enabled him to earn competitive rents from the sale of Swiss Army knives? Another unexamined prejudice, this time in cartoon form.