Maid service is included for the residents of Pomuch Cemetery in Campeche, Mexico, where a tradition dating back to Mayan times makes for a really memorable Dia de los Muertos. An old folk belief holds that poorly cared for relatives will become angry and walk the streets, so in order to keep the undead population at an absolute minimum, everyone buried in Pomuch is exhumed after three years, and their bones are cleaned and put into a wooden box to be displayed permanently at the cemetery. As a kind of family bonding ritual, relatives come together every year on Dia de los Muertos to give the bones another polish. This includes, by the way, any artificial hips, knees, etc that the deceased may have picked up along the way during life; all is sacred! It's thought that Campeche's tradition relates to a Mayan one in which people kept and venerated the skulls of ancestors.
Here's a video of some bones being cleaned on Dia de los Muertos. Around the middle of the video it seems like there's some confusion as to which bones belong to which grave!
According to Atlas Obscura, there is concern that as modernity comes to Campeche, the old ways will be abandoned.
In the words of one local man speaking of his children "I can't make them do it, but if they don't, I don't know where I'm going to end up."