doing a selfie with the webcam

First, that's easily enough to identify you from biometric data, and it's naive to assume it won't be resold. Second, I kept getting asked for ID into my 40s because I looked young. People don't all age in the same way, so this system will fail for people at the tails of a normal distribution - some 15 year olds will easily pass for 25 and vice versa.