I heard an interesting story. An old timer I worked with told me when he was a young man a few gas stations removed their spinners in their sight glasses and put dice in them. After the attendant pumped gas, they would wait for the dice to settle, and if the dice matched the last number of the sale price the customer won a prize or free gas. He said that this game did not last long before it was outlawed as a form of gambling.
So, has anyone ever seen this, or maybe found a few dice in a sight glass?