I had another version of this at the DMV. They needed to see bills that offered proof of my residence (ie power/water/etc). Turns out they wanted them to be mailed to you, which wasn't going to work because I do paperless billing for everything. So I printed them out and tri-folded them as if it had been in an envelope. People in front of me in line got turned away for using printed bills, but mine worked just fine.
Why?
This is obviously way less safe than using digital signatures, which are bound to me by SSO. Anyone could sign any document with a fake signature that looks just like mine, it would be very hard for them to do a digital signature associated with my account.
I get so much paper mail it's insane. Paper mail that I'm supposed to respond to with more paper mail.
Fuck that.