The New Yorker also insists on typographical affectations such as coöperate and reëlect. Most publications have a "house style." The New Yorker's is particularly eccentric, and I think they like it that way.
I used to think this was annoying and snobby, but after seeing the New Yorker deëvolve into a less funny BuzzFeed over the past couple of years, I long for the over-the-top snobbiness of the old New Yorker. At least it was a distinct identity.
Are there any magazines that recreate the snobbishness of old New Yorker?