paradoxper
Headphoneus Supremus
I won't pretend to have visited every country in the world but you are convoluting the topic at hand.Fair enough about the price for some of them. Looks like the specific ones I looked at were more expensive.
https://www.quora.com/How-do-I-use-a-cheater-plug-safely
There are entire countries that aren't grounded, you know.
This is where appliance classes comes in, furthermore, you may just assume all two pin plugs aren't grounded which is incorrect.