Any reason for encrypted /?

I am a big fan of linux and like trying out new distros now and then. I usually have my home folders and roots in a lvm atop an encrypted partition, but this tends to become cumbersome with every initramfs creation process being more alien than the last one.

sudo rm -rf –no-preserve-root / vs sudo rm -rf /*

As everyone knows, these are two deadly unix commands that both tell a machine to commit suicide. But what is the difference between the two? The first one deletes the root directory, while the second one deletes everything in it. Both are equally bad, but will the first one delete the filesystem because it deletes the root directory itself? What is the difference?