IPhone :: Why Can't There Be A "password" To Power Off It Or IOS Devices

"Please enter Password to power off." I was wondering if anyone had a possible reason why this isn't in the iOS devices features? If some one steals your device, all they have to do is power it down disabling the wipe, find, and alert features in iCloud. All apple has to do is add an option that allows the owner to require a password to power off the device. This way we would have the remainder of the battery life to locate, wipe, or send messages to the device. I encourage anyone that reads this post request this to Apple as a feature.