one thing ive seen done in lieu of a seating chart but with a sit down meal is the place cards were placed at the entrance and everyone picked theres up as they went in. It had our entree on it so the server knew and it discouraged people changing their minds at the last minute causing a potential catastrophe in the kitchen

also someone mentioned the seating of bridal party dates, I have always liked them being allowed to sit next to their date (if u are picky about the appearance and dont want that many people its not an option) but too many times ive been the date in the awkward situation of sitting with people i dont know.