People don’t show up.
If the crowd is a little thin at a non-seated party, that's an easy fix: Mingle more, turn up the music, and serve more drinks. If, however, guests at a seated dinner party or event don’t turn up, handle it subtly. Remove the place setting and put wine, a bread basket, or any other dish in its place. Plus, guests always can use more room to spread out at the table.