Not it's not hard, but it is significantly harder, and why introduce unnecessary additional complexity into my life? My ID is in my wallet. A sheet of paper do

Not it's not hard, but it is significantly harder, and why introduce unnecessary additional complexity into my life? My ID is in my wallet. A sheet of paper doesn't fit in my wallet. So I have to put the folded paper in a pocket, where it might fall out when I take out my gloves, or I forget if I put it in my backpack, and in which pocket, etc. A sheet of paper is extra. My phone isn't. And I sure as heck don't bring a phone with low charge to the airport... when I know I'm probably going to be using it for hours... and I've got my charger with me anyways in case I somehow did.