Its not identity theft it's bank fraud!
By continuing this stupid misnaming and shifting of the victim and the blame to the individual the real culprits and victims (the banks and other financial services that hand out credit (or your cash) without proper checks can continue to shift blame and losses.
Anyone requesting date of birth or mother's maiden name as a means of authentication for anything critical really needs to do something more sensible. These are essentially public information and should generally be treated as such. National Insurance (Social Security in US) numbers, driving licence numbers and passport numbers could all be usefully used a identification but are not suitable for authentication. That is they are useful to confirm who you are claiming to be but not proof that you are them.
Anonymous when I feel like it.