Gas Station Fills
How the scam works:
You need gas and stop at a full service station. You tell them how much you want, waiting in the car. A couple of minutes later the service is done. You have a look at the pump and pay the amount displayed. If you're nice, you might even give the attendant a tip. Where's the scam?
If you don't get out of the car or if they notice that you didn't look at the pump before starting the fill, the pump won't be set back to 0 (from the last client) before starting. The total will therefore include the amount from the previous sale which has already been paid by the last customer.
Because most people know roughly how much they pay for a fill, the attendant will most likely pull the scam when the prevoius purchase is not very significant (e.g. $10).
How to avoid:
Look at the pump clock as soon as the service is offered. Even better, do your own filling.
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