But of course it is.

Brendan H__ v. KatachiSF Inc. dba Katachi, No. CGC-10-501116 (San Francisco Super. Ct. filed 6/28/10). Personal injury action in which the defendants failed to warn the plaintiff that playing with a sharp sword displayed in its store would result in the plaintiff slicing his hand when he attempted to place it back in its sheath.

And in case any Brits were smugly thinking common sense is more prevalent on this side of the Atlantic, remember this – the introduction of the anti-stab knife happened here first…

(via Lowering the Bar)