You can carry most any corkscrew, pair of scissors, knife or perhaps even an unloaded gun in your checked luggage. It is the items you bring onboard as hand luggage that will get scanned for dangerous items. Therefore, if the seller wraps a package and declares what it contains, I see no reason for security to stop it from being delievered by air.
What I object about is that in many airports you get your boarding pass, check your luggage, go through security and then on the "inside" there are restaurants and shops which sell alcohol among other things. Dunno if they sell small scissors, but probably not. If someone wants to create a dangerous situation onboard the airplane, just buy a small bottle of alcohol and put it in your handbag which will not be checked when you board the plane. Once onboard, it is a simple task to smash off the neck and voila you have a very dangerous weapon, much more efficient than any cork screw or pair of nail scissors in the world.
