The phrase 'as a courtesy' is used in written English and can be used to express politeness or graciousness. For example: I stayed late to finish the project, as a courtesy to my boss.
Processing was done as a courtesy.
Breyer joined the majority "as a courtesy".
You may think this is being done as a courtesy.
As a courtesy, Nevins decided to meet Lewinsky.
Then Reverend Samuels, as a courtesy, wiped a smudge from David's forehead.
As a courtesy, other exchanges typically alert the agency to serious threats.
As a courtesy, he had sent him the question the day before.
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.
Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com