Apparently the idiot doper didn’t think through the idea that a sword is something you have to *learn how to use effectively*, just like most other tools. Having used swords for over 25 years myself, I couldn’t help laughing at the poor fool. What little I saw of him made me think, “Bud, if you tried that with me I’d have taken it away and spanked you with it. And you could count yourself lucky to still have your arm.”
Kudos to the shopkeeper for an effective, and even diplomatic, response. While using his own sword to take off his head or gut him like a carp would have given a certain satisfaction, it would have left a bloody mess that would have driven away customers. Well played.