You see seven swords just sitting in a hole and so you decide to steal them. They were just left in that hole after all, it's not like anyone was using them. And even if they were, they'll never know you were the one to steal them, right?
You steal the swords and realize they aren't just seven random swords, they're from the famous sword sets (せつ) they sell online. This particular set is from the Seven Samurai movie. Yes! What a great steal!