There are so many reasons to have proof of who you are.  
If you want to use health insurance, prove you have it by presenting a card.
If you want to shop at Costco… show your card at the door…  or you can’t get in.
If you want to drive, prove you’re a legal driver with a drivers license.  Don’t have a drivers license when you get pulled over?… Now you’re in trouble.
But… if you want to vote for the most powerful position in the world…
Don’t worry about it.  Step right up.  And if anyone gives you a hard time about not having proof of citizenship… label them a racist.  
Cuz that makes sense.
John Vogel