In the Lodge dance scenes with Rob and Laura the man visible seated on the far left of the image is Grant Tinker, Mary Tyler Moore's husband.
After Sally's musical number she loses her hair ribbon and has it in her hand when she goes to Rob & Laura's table. After the intermission she is seen replacing it before starting the next number with Buddy.
In the lodge dance scene, Buddy introduces Rob and Laura as, '... from New Rochelle, those dancing suburbanites Lester and Esther Bushmaster...'.