Maybe for testing the crash-resilience of software running on the node; but not necessarily for testing how the SDN autoscaling glop you've got configured responds to the node's death.

A panicking instance is still "alive" from its hypervisor's perspective (either it'll hang, sleep, or reboot, but it won't usually turn off its vCPU in a way the hypervisor would register as "the instance is now off"); while if a hypervisor box suffers a power cut, the rest of the compute cluster knows that the instances on that node are now very certainly off.