Ron - I was referring to the fact that merchants are not qualified to check IDs. In other words, it would be easy to make an ID that would convince them. That aside, merchants really don't want the additional liability. Right now, all they have to do in order for MC/V to pay them is to check that the signatures match. If they do, they'll get paid, even if the card is stolen. If the burden to proof that the card is used by an authorized person is shifted to the merchants, their liability will rise immensely.
Sam - I agree, it's quite annoying that we as customers have to force merchants to live up to their contractual obligations....another one is that minimum charge for credit card scheme. It's against their contract. That one is easier to deal with, though - let them add the additional charge to bring your amount up to the minimum and then dispute it. They usually don't want to have to pay the charge back fee again.
Bob, there are lots of reasons why one wouldn't want to show ID. For example, I certaintly don't want the average Home Depot salesperson to know my DOB, address, DL#, etc. ID theft is already a big problem. Quite a few state Attorney Generals actually advice consumers not to disclose any personal information, including ID, for credit card transactions. In your situation, you would not have prevented the thief from charging your card even if ALL merchants checked ID. There are lots of ways to charge a CC without even the opportunity for an ID check (and that's assuming merchants were able to effectively check IDs, which they aren't).
Look, the CC companies have made the decision for us. If you want to write 'check ID' on your card, please do so. Just be aware that if someone were to steal the card, they could still refuse to provide ID and the merchant would still have to process the charge (and 99% of them will). Personally, if I had a problem with a contract that stipulated that IDs must not be required for purchases, I would simply not use that provider. But if you're using MC/V, that's the way the contract goes. I believe Amex/Discover has a different merchant contract (though I believe Amex prohibits requiring ID if the merchant also accepts MC/V - not sure).
-Felix