that was likely a low tech scanner. Just because it says it scans for fingerprints doesn't mean it really does and just like in any other field you get what you pay for. I work on biometrics projects at my school and one of the labs I used to work in had a hand geometry scanner, made a dozen or so measurements of the length and such of fingers one of the older and less secure methods, it required an id number because while unlike fingerprint hand geometry is good for a one to any search. meaning that it will only confirm an id because mostly the accuracy is so low compared to what it would need to determine different people without combining other security vectors. Just keep in mind not all scanners are created equal and not all modalities, different biometric paths such as fingerprint iris and many others, are equal and they can be easily combined to increase security in a similar way multiple passwords adds security and it needs to be tailored to the application just like any other security approach. and just like all other methods of security it is a cat and mouse game.