Before the middle of the book the concept of dining fades away.  Tolkien never writes “dining room” – it is always “dining-room” which also has its own entry as an uncommon word and for the delight of fans of the hyphen.

• 01.002 kitchens, dining-rooms,
• 01.004 (especially after dinner,
• 01.012 Make you late for dinner!
• 02.001 went into the dining-room.
• 02.002 in the kitchen before turning out the dining-room.
• 02.002 in the dining-room by the open window,
• 04.012 in Bilbo’s dining-room that seemed so long ago,
• 07.094 or a dinner,
• 07.095 When dinner was over
• 08.066 all about having a most gorgeous dinner.’