Embalming got popular when long distance travel became practical. They no longer had to have a funeral and get them buried in 2 or 3 days. It enabled them to hold the bodies until relatives could arrive for the funeral. It got so popular that most people think embalming is required but in most cases it's not. It's just an added expense and a big money maker for morticians.
Steel caskets and vaults aren't required either. They push them on the family so the body will keep longer but that's not the real purpose of them. Many cemeteries require one or the other because they don't rot and collapse, leaving them with a hole to fill up. Wood caskets rot apart and collapse leaving a hole that needs filling later.
Cremation is FAR cheaper. We cremated my mother last month for $800. Sometimes you can find a crematorium cheaper than that. Urns are optional. If you want one, you can go as cheap or expensive as you like.
