These photos could be stolen and reused for fraud and identity theft.
Electronic IDs provide a much safer and more reliable way to check the identity of a user. Eg: every citizen in Belgium can authenticate HTTPS connections with his ID card.
When someone solves a problem in a particular technology stack in a suboptimal way, it is generally considered unhelpful to tell them they should have just used a totally different stack. "Why bother working around that registry issue in Windows, when you could have just used a superior operating system, such as OS X?", etc.
1. The US does not have a compulsory national ID. No, Social Security is in fact opt-in, it's just that these days most people are opted in without their consent. Passports are clearly optional.
2. The US is unique in the states/federal struggle, which has been ongoing since before 1776. One of the reasons REAL ID will never get adopted is because many states fight strongly against it.
3. There is a real question of jurisdiction. Does the Constitution grant the right for the federal government to force citizens to have an ID? If you invoke the supremacy clause, the states will invoke the 10th amendment right back at you :)
4. Do you really want the US to have a federal ID database? Between the Hillary emails, the OPM hack, and the general spirit in which the federal government seems to be operating, the last thing I'd want is for them to have more power.
See Wikipedia for more info: https://en.wikipedia.org/wiki/Electronic_identification