Also, in the case of the groom being adopted into the family of the bride, like Erich-nii-san, the family accepting the groom relieves the family of the groom of its duty to provide a dowry. Of course, it was still a common custom for the groom’s family to send congratulatory gifts as a return favor.
However, it seems the congratulatory gifts from the Baumeister household, that should have been sent, had not yet arrived for some reason.