Are you kidding me? Oh my goodness....
Listen folks... please...
1) Thumbprints can not be changed.
2) Due to #1, you need to protect your fingerprint data
3) You can change a credit card #, but not your fingerprints
4) If your prints are compromised, you are screwed
DO NOT SEND YOUR PRINT to ANYONE. Especially a grocery store!!!!!
What will they do with it? Who are you sending it to? Who has access to it? Who will be given this information later? Will it be on a laptop that someone steals? Or on a server that someone hacks?
Your prints are crucial. Software claims to help protect your data. This is NOT true. ALL software stores their encryption keys in MSFT's operating system. We all know Microsoft issues patches for their Operating Systems monthly.
It has been determined that the operating system will NEVER be secure. This is the reason you should never send your print to anyone.
There is only one solution. That solution is to store encryption keys in hardware, before the operating system boots up. This is called "PRE-BOOT" authentication.
Buy only computers with a TPM chip in them (Trusted Platform Module) it is like having a marine guard with an M-16 guarding a small safe in your computer. Enter your CC# into encrypted software to "auto-fill" out webpages. This software is included on these PCs with the TPM. It costs you NOTHING. This is an encrypted format for your credit card number. It is much safer and prevents any keyboard sniffing.
There is much to learn, but do yourself a favor and get a PC with a TPM in it:
http://www.chicagokitesurfing.com/identitytheft.html