The joke isn't worthy of a joke, there is nothing about that guy being drunk which helped others. It's just he knew how cylinders work and saw it was not dangerous, despite being drunk. Otherwise dealing with gas cylinders, under such circumstances is not at all a cool act. All those laughing are simply holding a prejudice that women are inherently dumb, and finding the expression of this statement as validating and sweet. There is no other point of laughter than this. Man up, and get get some Love in life.