There's a shoe store in my town where the sellers do this! They take measurements in the normal way, have you step on pressure-sensitive paper to make a print, and then say, "You've got significant curvature, so Nikes and Reeboks aren't going to work for you, but let's give New Balance a try." It's amazing. (The Shoe Shack in Dubuque, Iowa, for anyone who's curious.)