That is really, really funny.
I often see stuff (packaging material, etc) that's labeled "do not eat." It's generally stuff that I figure nobody in his right mind would ever consider eating, but I suppose somebody did.
On Harley Davidson's, the bikes have a thumbscrew device on the throttle that allows you to control the amount of effort required to move the throttle. Back it off all the way and there's no friction at all. Screw it in all the way and you can't move the throttle, something that should only be done in rare circumstances. Harley has a warning in the manual that says very clearly that the thumbscrew is not a cruise control device, and that tightening it too far can result in loss of control of the motorcyle, and death or injury.
Well, some numbnuts was out cruising in the country a few years back with the throttle screw tightened all the way. He came upon a tight curve, couldn't let off the throttle, and wound up in a field. He sued Harley, and they settled out of court.
Every time I've bought a new gun, I've read the manual, and it's always about 10% instructions, and 90% safety warnings about things that should be obvious. But that doesn't stop the anti's from suing the manufacturers for selling unsafe guns.