A mail conversation between RC and HBS clarified the reasons HBS has for disappearing bodies.
The paraphrased version:
- Dead bodies can cause clipping issues where their sprites collide with other sprites.
- If bodies can be walked through, that too would cause clipping issues which they felt looks crappy.
- Solid bodies that block the path could result in roadblocks, coding around that would take programming time they preferred spending elsewhere.
- Leaving bodies on the screen would give the impression they could be looted, while they can't.
- Specific NPC deaths can still be programmed to leave behind bodies and/or items in the Editor.