Honestly, I'd be afraid this requirement (which would add one more task to the mailroom's list) would be more likely to hasten the end of being able to send anything physical. You can go onto your account and check that the letter has been scanned in.
Hi Ashley! While this may be helpful to sponsors, Sarah brings up some good points, as well. However, I don't make the calls as far as what gets implemented, so I will certainly pass this feedback along!