Cash Crusaders collecting identity documents

Went into the cash crusaders store this morning to have a look around. Decided to buy Binoculars they had available there. When I got to the cashier she asked for my I.D to make a copy. When I asked why she said that it is policy to make copies of anyones I.D that purchases something for more than R100!! Why exactly are you collecting copies of I.D's? With all the I.D theft going on, I for one will not show my id to buy anything, let alone have a copy made of it!!! Utterly disgusted and will not visit any of your stored again.