Is there any legal reason for an obituary in a newspaper?
Publishing notice of the death has several purposes. One reason is to provide notice to the friends and family, but also local businesses, creditors to an extent, even though you formally mail them notice as an executor. Publication by itself even without a person reading it creates constructive notice of the death, meaning that it might make it harder for people to try to come forward either to claim money, a debt, a property interest and so on after the deceased estate is probated.