I'm almost certain that if most of these people found out they had cancer and would die unless they got a treatment and (1) with the treatment they would have only a 20% chance of survival, (2) the treatment would be very painful, (3) the treatment would be very expensive, and (4) if the treatment worked they would be unhealthy for the rest of their lives; then almost all of these cryonics rejectors would take the treatment.

It's painful, expensive, leaves you in ill health the rest of your (shortened) life, and you've only got a 20% chance?

Why would someone take that deal?