 Why doesn't the narrator use his powers to win at slot machines?
Mine was no satisfaction, never earned me a penny—and now it had me fighting for my life in ... This being earlier than I usually get up, it seems all I did during the night was feel my way past the escapement and balance wheel to see where the notch for the alarm was. I even went to Las Vegas to try my hand, so to speak, with the ratchets and pawls and cams and springs on the slot machines. But there's nothing delicate about a slot machine, and the spring tensions are too strong. One went to a battery and the other to hard round cylinders taped together. I'd be a man not to be trusted, a prying man, a man literally with gimlet eyes.
 The mechanical workings of the slot machines are too difficult for him to control.
 He did use his powers to win at slot machines. He got himself banned from casinos.  He thought about using his powers to win at slot machines but then decided it was too risky. He was afraid of getting caught.  The mechanical workings of the slot machines are too difficult for him to control.  He did use his powers to win at slot machines for a while. Then he became addicted to gambling and had to join Gamblers Annonymous.