May I please see your I.D.?

Identity theft is bad. Having you credit card stolen is bad. So when someone asks to see my ID when I use a credit card, I oblige without much thought. However, while picking up some pizzas recently at a local Italian eatery near my house, I realized just how stupid it is to ask for someone's ID when they use a credit card because this practice only prevents some forms of credit-related theft. An example: Two months ago, I dined at this same establisment, but we sat down and ate our meal in the restuarant instead of getting the meal "to go". So when the check came and I paid with my credit card, did the waitress ask for my ID? No. In fact, I have never been asked to show my ID when paying with a credit card at a restaurant. Home depot asks to see an ID when I use my credit card, but then again, if I use the self-check at home depot, no ID required. The grocery store clerk never asks to see my ID, however, when using the self-check at Albertsons the customer is asked to key in a zip code. This also happens at some gas stations. Most department and clothing stores never ask for an ID. In light of all these inconsistencies, it seems to me that only asking for an ID in very few situations is really ineffective and only foils a small percentage of credit-related crimes. So what's the most effective way to stop these crimes? I don't have a fucking clue, I'm an academic and I don't have the answers to any of the world's real problems.