I like the trope of Earth turning into a giant nature and history preserve after humans colonize space. Naturally, not many people are going to die on Earth any more, and certainly few will be buried there—if at all, only the extravagantly rich who can afford burials at graveyards grandfathered into allowing internment on what is now public land.

If the gods of the afterlife derive power from souls who come to rest on Earth, they’d certainly have cause to panic when their new arrivals dwindle to a handful of elites—elites who are probably just as unsettled by their lack of numbers in their afterlife cohort.

There might also be a handful of disgruntled dead hikers who are less than thrilled to realize nobody ever found their body after they fell down a cliff or got lost off a trail. They’d probably be of at least moderate means to have been able to afford an Earth vacation, but they probably never anticipated being expected to cooperate with a bunch of eccentric trillionaires and/or fiercely traditional religious people who insisted on terrestrial burial.

Imagine the Afterlife Gods gathering them all in some garden to recruit them to go on a mass coordinated interstellar haunting to try to convince humanity that its birthplace is also its expected resting place.

Perhaps the “afterlife” gods of previously uninhabited planets and interstellar space (space burials), who were busy being blissfully nonexistent before a bunch of dead humans started showing up, are less than thrilled. (Perhaps some of them are thrilled, though.)