out of courtesy (to one)
With kindly consideration or regard (to one); done so as not to offend or be impolite to one. I'm willing to overlook the incident this once out of courtesy to your father, but I won't hesitate to put you in prison if it ever happens again. We're letting him join in out of courtesy, not because we want to be friends with him.
out of courtesy (to someone)
in order to be polite to someone; out of consideration for someone. We invited Mary's brother out of courtesy to her. They invited me out of courtesy.