Years ago I read about a scam where people were tampering 7-segment displays in gas pump stations (e.g. by altering one segment a "9" will be displayed as a "5"

Years ago I read about a scam where people were tampering 7-segment displays in gas pump stations (e.g. by altering one segment a "9" will be displayed as a "5", an "8" as a "6" and so on), so you got less gas than what you paid for. This worked at least in two ways: - By showing the wrong price/quantity (1.980€/l would become 1.560€/l) - By showing the wrong quantity dispensed (39.8 liters would become 35.6) I guess the lesson here is to never trust a 7-segment display until you can confirm all segments are working.