As I said, I don't think it worked like that. I think they enjoyed the afterlife as normal and were summoned at the time of need. The alternative seems evil to me, even if they chose that willingly.
In what way is it evil? It's unfortunate and sad, but those aren't synonymous with evil. Martyrdom, by its very nature, requires unfortunate but willing sacrifice.
I'd just like to point out that saying that something unsupported is the case unless someone else can prove that it is not is an utter failure of logic. - Kish