I studied up and wrote a big paper on this end of dying for my MDiv. I was quite shocked along the way.
One of the sources I read compared this business to other commerce, and determined prices basically were about 3 times too high because there were 3 times too many of them, working at 1/3 capacity (think about days the 'homes' are busy, not very often, way below capacity). That author suggested the only way that could work long term was overt or covert collusion.
Another source suggested that most other service aggregators passed savings on to you - decorators, landscapers split source discounts, etc. as part of their service. Yet funeral folks will sell their package services, and still mark up every little thing along the way, such as placing obituary - marking up the paper's fees, typically 10% for that - rather than discounting for bulk.
I also studied the, say fittings used for embalming functions - not my wife. Lots of bits that looked like those big drywall anchors, orbit hooks for smiles, etc. No one enjoyed my paper and powerpoint, but we all learned.
For history (only read a bit), it seems this whole business of embalming and 'looks natural' only came about around the Civil War time, as 'we' got to where there was a fair chance a body could return from a good distance in a chemically managed window - by trains, a method that for the first time on land, did not have to stop and rest.