alt Hacker NewsThis is underselling it -- an adult can sell these yubikeys untraceably, pocket the cash, and never think about it again in their life.
If we tie the person's identity to the token (THIS IS A BAD IDEA) then if underage use is detected, the adult who sold the token can be prosecuted for selling adult tokens to minors.
An adult could also sell alcohol or drugs to minors so what? Should we add a code to every bottle and require passport to buy them?