I got my my hard drive wiped recently and when I went to register my fingerprints on restart, I said that templates already existed. Can fingerprints be maintained through a disk overwritten in zeros and ones? Or did I get ripped off?

Are you saying you paid someone to do a wipe and fresh install of your computer?

You have a biometric reader (finger print scanner) and it for some reason still recognizes your fingerprint even though you had the drive wiped?

I think that the finger print reader has a built-in memory. If that's the case, then I have no idea how to solve it. O.o

The fingerprint readers usually work to halt the boot process' so they use memory that is on the main board and accessible before the boot loader starts. Wiping the hard drive will not effect this memory because it is not part of the hard drive. The memory for this type of device and usually be cleared by a utility supplied by the vendor or by using jumper switched on the main board of the computer.