Is it normal to collect human bones

My boyfriend has a collection of human bones. He has 4 complete skeletons and 11 skeletons that are atleast 80% complete and then a bunch of random bones. He inherited the skeletons and then buys or "picks up" the rest of what he has. I think it's gross and spooky and insensitive, he thinks it's funny and "cool". No doubt the collection is worth a lot of money, somehow, but I still think it's grimy.

And it's never fun to come over to his place to find a box of decomposing bones covered in flesh eating beetles.