Oh that happens everywhere... people only show up when the food is served and disappear when they've eaten. They don't help set up or tear down.I know the feeling...I have several standby helpers making sure that the food is on the table when they are ready to eat...then suddenly disappear when the meal is over.
My family was in shock one year when we told them to show up at one certain time for the food and they got stuck helping to set up because that time was intentionally way early... and those of us that normally set up, didn't. We showed up, ate, and left. The tables were turned on them