Since ancient times, when a messenger brought a new, he was welcomed, fed
and housed for the night. One was taking care of his mount for free, if he was
not , as Philippidès, came running to Athens in 490 BC. of course.
Later, it became usual to give a kind of " tip " to the one who was
" mandated " to bring a new, even if the word " tip ** " appeared only in the 18th
century
Thus was probably born the use to pay for the receipt of a letter and
not its dispatch.
Wanting to pay for sending a letter was then perceived as a total lack
of manners : it offended its recipient implicitly meaning that he was not able
to pay for receiving his mail. Noblesse oblige, regardless of nationality.
That certainly complex mixture of financial interest and self-esteem tinged with
pride that made difficult the use of the first postage stamps in their
emissions.
** BTW, did you know that " tip " comes from " To Insure Promptness ".
One day in the 18th in England, a restaurateur settled on his desk a pot with inscriptions To Insure Promptness. This pot was designed
to receive some pieces of pressed customers who wished to be served faster. So
that TIP..