左利き(hidarikiki)

I found out that the Japanese word 左利き(hidarikiki) means both left-handed and (heavy) drinker. I wonder what is the connection between someone who drinks a lot and the left hand. Do they get so wasted that whatever they do looks as if executed by the left hand of a right-handed person or does it mean that lefties drink more than righties? Or maybe that Japanese drinkers use their left hand to raise their glasses?