They dont steal your ID by cloning your passport, they steal it by getting just enough Personally Identifying Information to be able to start up credit cards and other loans that are tied to your credit history, without your knowledge. By the time you find out, they've run all the credit lines to the max and then you have to go around to all those companies and prove you didn't make all those charges. Then you have to get all of your account numbers changed, because you don't necessarily know what the hacker has compromised.
Most of the information necessary for opening accounts is on your driver's' license. Pretty much the only thing it is missing is your SSN. And in some cases, a valid state license number can be used in place of that