This is not quite true. In Nevada, the ballots were mailed to every registered voter and on a completely unsolicited basis. (I did not even know one was coming; it just showed up one day.) I knew what it was because I had done mail-in voting in the past, under the format you are suggesting, but I was still surprised to get a ballot on an unsolicited basis. It caught me off-guard, but I kept it because after looking it over, it was clearly legitimate. I did have to take a moment to figure out what was going on, as this had never happened before.
In any case, I am sure that many, many voters who had moved on to other addresses or other states, or who had passed on received ballots. Our driver licenses here are for five years and you are encouraged to register to vote when you renew or first receive your license. it is a 3 second process consisting of checking off a box or saying yes to an encouraging clerk. To my knowledge, there is no way to unregister; you simply stay on the rolls until the end of time. My guess is that over 10% of the registered voters are long gone or have moved on or at least have changed local addresses. That is a lot of potential votes to be king of floating around out there looking for someone to find them and cast them.
No reporter has ever written an article on how many ballots are returned as undeliverable, or about what precautions are taken. My guess is that a lot of them are left lying around mail rooms in apartment complexes.
The "Blank Magazine Subscription Postcard" metaphor? It definitely fits, as far as our state goes.
