Free postage!
All they had to do was sign the envelope and it was free. Today they can have the name printed on envelopes as the volume of mail for a President or ex-President is nothing short of massive! But for all of their lives they will never have to pay postage. Until the 20th century that was one of the few perks that they received after office..This practice has given autograph collectors a lot of signatures. Until well into the 20th century every letter was signed for free postage. Here you see John Quincy Adams signature on a letter ..