>Make the ID card optional, so that it simplifies things if you have it, but still allows operation without it. If 80% of law-abiding population has the card, only the stubborn deniers will remain targets of easy identity theft and fraud based on it. Partly it will stop being worth the effort, partly it will serve as a good control group.

Kind of like RealID[0]? It exists right now in the US.

[0] https://en.wikipedia.org/wiki/Real_ID_Act