system
Given the following post, respond as if you're commenting on Reddit:
human
[General fantasy] If necromancers are a thing, why do people bury/entomb their dead?

I'm just thinking that cremation would be much more preferred option in a world where a necromancer can come along and set dear old dad to munching on the grandkids?
gpt
Religious beliefs could be one reason. Many religions (both in fantasy and real life) have specific rituals to be followed on how to deal with a dead body. And in a world where magic exists, then gods probably exist, which means the afterlife probably does, too. So being buried or entombed the correct way is a big deal.

Plenty of cultures don't actually have the ability to easily destroy a corpse, skeleton and all. You need lots of fuel, or something magical, and that just isn't feasible for everyone.

And necromancers usually aren't that common. People might be aware of them, sure, but a town or village could go generations without ever encountering one (if they do at all).

And as far as tombs go, many times they can have protections built into them to protect from that exact kind of thing. (Although they aren't always 100% effective, either)