WHAT ID NECESSARY FOR A LOYALTH CARD?

Could someone at Checkers please explain why it is necessary for me to give personal data, such as my ID number, to get a Checkers loyalty card? Data handed out to all and sundry is open to abuse. I have no clue as to why this would be necessary. It is not as if I am asking to borrow money - I am allowing them to reward me for using their store. Needless to say - I will not be being loyal to Checkers.