It's not for your protection that the merchant violates the agreement they signed. It is for their protection as fraudulent use of a card does not cost the legitimate holder a dime. I refuse all requests for DL or other ID. I have challenged Wal-Mart thru MasterCharge and received an apology from corporate and they no longer request additional ID. Challenged Dobbs Tire and received a written apology from corporate. The best was Lowe's. I challenged them when they demanded DL after purchase was approved by MC. I refused and they withheld merchandise but did not reverse charge. They settled for $4,650.00. The disputed charge was $27.54. How many times have you seen the merchant compare the card sig with the charge sig? That is required by the agreement but is almost universally ignored. If the card is not signed, it is considered invalid and the merchant must require that the card by signed in their presence before acceptance. Another consumer fallacy is marking "See ID" on the card. That makes the card invalid as it has been altered. I learned quite a bit about the proper acceptance of CC's during the negotiations w/Lowe's attorneys.