Yes, that is what I heard. There are people who do not know that speakers should be plugged into your receiver and not the power outlet on the wall...then cause explosions and fires when they plug them into the wall outlet. The double set fits perfectly (or so I have read) and the singles will fit one at a time. Even the grounded outlets are not safe from banana plug stupidity, since the grounding prong is simply ignored.
Although I just read there IS a legal version of the banana plug in Europe now, it has a plastic prong sticking out to the side of the banana plug where it will not interfere with using it in a binding post but will prevent it from being stuck into an outlet.