For about six years I have carried an article in my wallet that I cut out of a newspaper, which states that additional ID is not required for a purchase with a signed credit card. I have had to show this article a number of times and, even then, some will insist it is "store policy". If that happens, they lose a sale.

One thing I wish is that credit cards provide a slightly taller block for to sign in, and that they would NOT place your card number squarely in the middle of that signature block!