The crazy thing is that this isn't limited to human remains.

Fake cameras often cost more than actual cameras. Fake food is more expensive than real food, which is then wasted.

I heard that they just used real ghosts 👻 too 😱 /s

The more interesting tidbit is that this is actually pretty common. The prop house using real skeletons was actually pretty common and not unique to this production. The notable thing about this film was the sheer number of skeletons that they used, so they basically scooped up everything that was out there, and how much the live actors actually interacted with the skeletons. It wasn't particularly unusual for skeletons to be used as props.

Really, just about any time you saw a skeleton on screen before the 90s or so, it was probably real. A lot of real world props and decorations also used real skeletons, sometimes to the surprise of the people using them. For example, if you rode the original Pirates of the Caribbean ride at Disney Land, you saw real human skeletons.

Pirates of the Caribbean in Disneyland also used medical skeletons. It wasn't that long ago that they were really easy to purchase, a couple instructors at my university had full skeletons and would bring them in for class. I wanted to buy one just to keep in my closet as a joke, but beer came first.

Ah, so not the whole we are both in the pool so if a light falls we are both dead.

Toby Hooper, always pinching those pennies!

Hmm wouldn't they have some sort of smell left?

That's a good point so I wonder why there have been instances in which next of kin were notified that their loved ones' bodies were used in horrific ways

I don't think that's 100% true. The guy that famously (posthumously) plays Yorick ('s skull) is not anonymous. (I just have problems with remembering names.)

Also, posthumous organ donation isn't necessarily anonymous.

Except they are not, oil is made from dead compressed plankton