Ah Zombie, I can see it as a theft control though. If the valve is shut of and not easily seen, someone quickly riding away with your scooter will be in for a surprise when it runs out of fuel.
Also a shutoff valve saved my life a long time ago when my buddy let me ride his supped up trailblazer and I was just going out of control off into the woods when it died out. He forgot to turn on the valve for me.