You can buy (though not from Homebase) a flex with a 13A plug on one end and just wires with stripped ends on the other. Very handy if for some reason you can't, without hunting, find the bits you need to make up a suitable cable. Much the same, safety-wise, as something with a plug on each end.
You don't leave such things where kids can fool with them, but they have their uses in a few situations. And require care.
After many warnings from my Dad, I became quite paranoid about the many risks involved in driving a car, and probably avoided many problems as a result of his advice. But I still had to learn for myself, and once skidded into a hefty wooden road sign after hitting a triangular pile of gravel near the centre of the road at the junction of three country roads. Probably the idea was to choose a good line through the turn to allow me to keep my speed up, but it was dark and the gravel wasn't obvious until too late.
Deliberately exposing everyone to a (non-fatal) shock as a demonstration might go some way towards persuading people to take more care.
ISTM that lawyers think that more laws are the cure for all problems, just as IT people think the same about more computers. Human nature, I suppose. If all you have is a hammer......