I agree entirely that it is a great idea for more serious / risky industries! Any transaction or meeting with risk that takes place without supervision or security; absolutely!
But I don't think it should replace identification validity entirely. I think on a smaller scale, for issues without much risk in which a person is required to provide identity, they should have the option not to.
I think it's a great idea for things in which verification is absolutely necessary for safety issues. A replacement, though? I, for one, wouldn't want to hand over my fingerprint several times a day. Feels a little cattle-like.
But that's just me. Thanks :)