It can be funny to watch people in the USA have "new" concepts forced upon them that the developed world has been using for over a decade.
Smart cards, that is what they are called, are unpowered. They do not do anything unless they are brought close to a reader. Perhaps you have heard of NFC? The N stands for near. When this unpowered card is sitting in your wallet, it is not irradiating your favourite body part. If you keep them in your wallet they will not work because a reader won't be able to make sense of multiple replies at once.
I think I have 5 smart cards on me. A debit card, a credit card and a debit card that is linked to my Vodafone account and 2 work ones hanging round my neck.This is neither new or particularly advanced. I know that I could get them onto my phone so that I didn't need to carry them but they are secure and convenient enough at present. My phone is powered and so might be readable at a greater distance. That is not something I currently need.
As for the people who got rid of all their plastic and unwanted signs of modernity, consider the fact that the CIA, NSA, FBI or whatever other criminal groups you are shying away from could satellite track you. GPS bugs are pretty small and easy to hide nowadays. Or perhaps you are of no interest to them and you have opted for an unnecessarily less easy lifestyle - or is your first name Theodore?