A while back I wrote a node for this page. It was deleted shortly after, or so I'm told by the status messages on the right side of my profile.
Just the other day I came back to E2. I can't remember what my original node was in the slightest. Here's a new take on this:
A secondhand coffin is a curiosity. There are three ways one can come into existence:
a) Someone was thought to be dead, but in fact was not., and they were put in the coffin before this was noticed.
b) Someone was going to be buried, but the coffin was stolen first. With them in it.
c) Someone was buried, and some graverobber dug their coffin up. Then the body was somehow disposed of.
(This list excludes coffins that have never had a person in them - while a coffin that was stolen before someone was put into may well exist, it's not technically used.)
So, more likely than not, the reason you have a secondhand coffin was because someone stole the coffin. With someone inside it. With that in mind, why would anyone buy a secondhand coffin?
a) Morbid fascination with death.
b) It's probably significantly cheaper.
c) Supporting the local black market.
d) They really, really hope that the answer to how the secondhand coffin came about was option a, above.
A secondhand coffin is not like almost any other object. It only exists due to extraordinary circumstances. It is, in essence, an artifact, of the thin line between life and death. Cherish it - and tip your "supplier" well!